Theres a small growth like lump in the back of my throat thats starting to look yellow in color. what is this im scared its a cyst?

Probably not.: It doesn't sound dangerous, although I am not sure what you are seeing. Yellow lumps make me think of pus? but it may well be a local area of altered lining due to inflammation or some kind of injury. If it is wedged in or near the tonsil it may be a clump of particles which can be dislodged by gargling.

Cyst: Usually one of two things a mucinous cyst which is benign and will usually go away or some lymph tissue swelling. The back of your throat has lymph tissue that will swell if you have drainage or an infection. Is your throat sore? If this is all recent activity likely not of concern, but if if persists you should get it checked.