My cat is also around 2 years old. He shed and sneezed a lot last year. I got Chlorpheniramine 4mg per tab on Amazon for $5. It can be split in half and dissolves in water + wet food. I have no issues after that.
Vet recommended half of Zyrtec but Chlorpheniramine works well.
I'm still waiting for my post to be approved since it has a link. If you can't afford the vet, you should call your local shelters and see if they'll accept stray cats that are sick.
I have two cats. One eats pate and throws up shreds. The other eats shreds and dislikes patte.
Friskes Prime Filets seems to have a lot of shredded meat with some gravy.