I'm really sorry to hear about your girl Meeka's episodes of flinching and grooming/licking of her front legs and hindquarters.
I know that you believe that she does not have fleas because she was given a flea bath and only goes out on a leash, but sometimes fleas are able to hop on quickly even with a short time outside. Flea baths will kill any fleas on her at that moment, but they have no residual efficacy, so new fleas simply hop on your clean kitty.
The most common reason for increased itchiness and grooming in cats is flea allergy dermatitis. Flea allergy dermatitis is horrible. If you don't see any fleas you might not have a huge population. And in allergic cats there doesn't need to be many, it only takes one bite a month for an allergic cat to itch like crazy. In many cases we don't see fleas because kitties "eat the evidence" with their excessive grooming. If you have other pets who aren't itchy they may not be allergic. Ideally I recommend topical flea products be applied every 3 weeks in an allergic cat when fleas are at their peak, summer and through late fall, or with an active problem and then monthly as a prevention. Many over the counter products have a problem with fleas being resistant and some can be down right dangerous. I never recommend any products that Hartz or Sargent's make. I recommend Advantage II or Frontline Plus, or the new Seresto Flea collar. I don't normally recommend flea collars, but this one really works and lasts for at least 6-8 months. All pets in the house must be treated as if you don't the nonallergic ones serve as a flea reservoir for the allergic one and you'll never solve your problem.
Inhaled allergies (to pollens, dust mites or mold spores) are another possible reason for excessive grooming/scratching.
To control allergic symptoms you can give her:
1) Benadryl (diphenhydramine only, the combination products with decongestants and acetaminophen are toxic to cats) at 1mg to 2mg per pound of body weight every 8 hours. That's a half of 25mg tablet every 8 hours for a cat that is 8 to 15 pounds. Benadryl is very bitter and some cats will drool excessively or may even vomit because of that. That doesn't mean it is making her ill, she just hates the taste. If that's the case with her try a different antihistamine,
2) Chlorpheniramine at 4mg twice daily.
3) Zyrtec (Cetirizine hydrochloride) at a dose of 5 mg per cat given orally every 24 hours. Make sure it is NOT the formulation with a decongestant (such as Zyrtec-D) because cats cannot tolerate decongestants.
Combined with high doses of omega-3 fatty acids antihistamines work synergistically to relieve her itchiness. I like 3V caps or Derm Caps omega 3 fatty acid products as they are reputable, high quality products. I recommend a dose based upon the EPA portion (eicosapentanoic acid) of the supplement as if we do that the rest of the supplement will be properly balanced. Give her 20mg of EPA per pound of body weight per day. For example an 8 pound cat could take 160mg of EPA per day.
Antihistamines and omega-3 fatty acids work synergistically, better together than either one alone. These should help reduce the itch. Be aware that antihistamines can cause drowsiness or hyperactivity which should resolve with continued use.
Food allergy is another reason for excess grooming. If she is not improving with flea control and antihistamines you might wish to try a hypoallergenic food for 8 weeks or so. My suggestions are Hills Z/D or Royal Canin Duck and Green peas. She will need to eat only that food, no other treats or foods during her food trial.
Over the counter foods may be labeled hypoallergenic but they are unlikely to truly be so.
The trouble with "limited ingredient", "hypoallergenic" or "low allergy" pet store brands is that the same machinery is used on multiple lots of food without sterilization cleaning in between. So for example even if a food says it has salmon and rice if the previous batch had beef and corn then you will get traces of those ingredients in your bag of food. Not a big deal if your cat isn't allergic to those ingredients but a waste of money thinking that the food was hypoallergenic, and not good for your cat if those happen to be allergens for your cat.
The veterinary brand true hypoallergenic foods are more expensive because it isn't cheap to thoroughly remove all traces of a previous food mixture from the machines used to process food or to hydrolyze the proteins in the food. And the only ingredients in that food, even at a trace level, are what is listed on the bag.
If there are other cats in the home that she doesn't get along with or outdoors that upset her perhaps this is stress related. If so a product called Feliway, which is a synthetic version of a calming feline pheromone, may help. You can purchase this from petstores or online.
Since she doesn't go outside much other parasites like Cheyletiella or sarcoptic mange are possible causes as well, but much less likely unless you have another pet that does go out and could carry them in.
For now I would start with continued flea control, an antihistamine and omega 3 fatty acids. If she's not significantly better in 2 weeks then it's time for a veterinary examination to look further for problems and/or a hypoallergenic food trial.
Please let me know if you have further questions by replying to this post.