What is wrong with my cat?

My cat is very large. She is probably 20 lbs. Besides that, a few days ago, she got this giant wound. I don't know how, but she has it. She was still very active and ate and was lovey so I just treated it with neosporine and wiped it down. But today, I come home and there is bile all over the carpet. She threw up about 5 times when I wasn't here and once when I was. I'm very worried and if you could diagnose her and give me tips on how to make her better, that would be great. I would like tips not about going to the veternarian. if she get's worse, of course I'll take her, but I don't want to spend a lot of money just yet. So please, help me. I'm very worried..thanks.