Hello, my name is***** and I have over 20 years of experience as a veterinarian. I'm sorry to hear that your girl has been non-weight bearing lame limping on her right front leg for at least 24 hours.
I am sorry I cannot help with a phone call. The states/province I am licensed in do not allow me to communicate via phone calls, unless I have previously physically examined a pet. I could lose my license for doing so. I suspect many of the veterinarians on line now have the same restrictions, thus you have not received a phone call.
I don't want you to think we are not concerned however and if you would like we can discuss her problem this way.
If your girl goes outdoors or has animal friends in the home with her the most likely cause is a bite or scratch puncture wound that has turned into a painful abscess.
If she goes outdoors other sorts of trauma such as a fall or being hit by a car are other possibilities.
It is difficult to tell from the pictures whether it is the way she is holding her leg, but it appears there is some swelling in the area just above her wrist joint (carpal joint) on that leg, and she is definitely guarding her leg.
Her abnormal conformation could be due to an abscess, muscle or other soft tissue trauma (torn ligaments or tendons) or non comminuted fracture(s) (doesn't break the skin).
A tumor in that area could also cause swelling and interfere with her ability to move normally.
Cats are pretty tough and refusal to use the leg at all means that she is in a lot of pain. I would expect some improvement with 24 hours of rest and that has not happened.
Given your girl's symptoms I highly recommend that she see a veterinarian for an examination and radiographs of the area, possibly as aspirate if it feels like an abscess.
I don't necessarily believe that this is an emergency unless she is refusing to eat or drink, but she should be seen today.
I do recommend that she see another veterinarian if her veterinarian is fully booked though. In the meantime confine her to a small bathroom or bedroom with his food, water and litter box so she cannot further injure himself.
Unfortunately cats don't tolerate the over the counter pain/anti-inflammatory medications we take.
In an emergency situation one dose of 1/2 of a low dose (81mg) aspirin can be given. Cats lack the ability to metabolize aspirin so one dose can last 3+ days. But aspirin doesn't control pain very well, interferes with clotting ability and can lead to stomach ulcers so it is not recommended for possible fractures. A veterinarian can prescribe much better medication for pain.
Best of luck with your girl, please let me know if you have any further questions.