My uvula is deviated to the left, could this be serious? could i have a tumor impinging my vagus nerve? i don't have any other symptoms.

You're fine: I see that you are a first year medical student. Deviation of the uvula is a marker for a cranial nerve palsy, but when you eventually see it in real life, it's spectacular and the movements of the other throat muscles are obviously abnormal. Few uvulas are truly straight. You'll also learn that you have palpable lymph nodes in your neck that may not be in the anatomy book -- they're okay too.