How To Recover From Sunburn?

hi doctor, i am rahil a 16 year old guy .My problem is that i look older than i am, i have total sunscreen allergy, my lip size is also little large and my complexion is between brown and dark brown it is because of that sun allergy, at my childhood i was quite fairer. Plz reply some solution about the above mentioned problems. How to recover from sun burn thing, reduce lip size and look what i m