The enlarged liver is likely the reason she is vomiting and not interested in eating. When the liver is not working right it makes you feel nausea but she should be willing to drink.
If the shot was a steroid this might bring on pancreatitis which you can read about here
http://www.peteducation.com/article.cfm?c=2&aid=335
which might make a dog unwilling to eat or drink as it would be painful to do so.
Your vet can give her fluids, and/or a shot of an anti nausea med or stomach soothing med to help with her current situation.
There are liver supporting supplements such as Marin or Denosyl that might help too
http://www.thepetwellnessclinic.com/marin.htm
An ultrasound would tel you what the liver looks like, if there is a tumor in one spot, if there is a liver inflammation or disease spread through out it etc.
Often you have no clue on a liver disease until you get to the point where the liver isn't functioning enough any more to keep the dog going. You can have a dog that has liver disease but as long as enough of the liver is working your'd never know, unless you did blood work, until the dog got sick enough to show symptoms.
As cash flow is an issue, check with your local humane society to see if there is local low cost vet care, ask your vet if you can do time payments or here are some groups that might help you afford the vet bills:American Animal Hospital Associationhttp://www.aahahelpingpets.org/" Through the AAHA Helping Pets Fund, veterinary care is possible for sick or injured pets even if they have been abandoned or if their owner is experiencing financial hardship."Angels 4 Animalshttp://www.angels4animals.org/"Our services range from financial aid to complete treatmentto those pets and pet owners in need."Care Credit If you qualify this may work well for you.http://www.carecredit.com/A credit card company for health care, including veterinary care."With a comprehensive range of plan options, fortreatment or procedure fees from $1 to over $25,000, we offer a planand a low monthly payment to fit comfortably into almost everybudget." They have a zero interest program if you pay within a certain time frame and they list the vets who work with their product.God's Creatures Ministryhttp://www.all-creatures.org/gcm/help-cf.html"This fund helps pay for veterinarian bills for those who need help."Help-A-Pethttp://www.help-a-pet.org/home.html http://www.help-a-pet.org/"Our efforts focus on serving the elderly, the disabled, and theworking poor."IMOMhttp://www.imom.org/"We are dedicated to insure that nocompanion animal has to be euthanized simply because their caretakeris financially challenged."The Pet Fundhttp://thepetfund.com/"The Pet Fund is a registered 501(c)3 nonprofit association thatprovides financial assistance to owners of domestic animals who needurgent veterinary care."United Animal Nationshttp://www.uan.org/lifeline/index.html"The m ission of LifeLine is to help homeless or recently rescuedanimals suffering from life-threatening conditions that requirespecific and immediate emergency veterinary care. We strive to serveGood Samaritans and rescue groups who take in sick or injuredanimals. In certain cases, LifeLine can also assist senior citizensand low-income families pay for immediate emergency veterinary care." They also keep a list of local and national help resources herehttp://www.uan.org/index.cfm?navid=163
More groups here http://www.speakingforspot.com/helppayingforveterinarycare.html
Hope this helps you!
Dog Expert:Rescue, Train,Breed,Care
30+ yrs dog home vet care & nursing, rescue, behavior&training, responsible show breeding, genetics