Swollen Vent HELP!

I just bought crestie a few days ago from a reptile store/dealer. I went in to buy my first crestie and the guy offer me a deal to get rid a crested gecko( the one I have now) He told me it's been in the store for long time and needs a home. I reacted to see it and the gecko was tailless and it i noticed it is a boy, it was really skinny. So i thought i can get it back to it's normal weight with no problem.

I got "Treeko" for $20, really really cheap. Then i get home to set his tank and i realize his vent it kinda swollen and it is starting to worry me. Does he have Hemipenal Prolapse? or something else, and is there to treat with out going to the vet, because i can't afford it right now.

I tried doing the bath methods from one of your videos just to see if it will help(hopefully it does).

If you need picture let me know.

please let me know ASAP!
Thanks, Keon