help!!!

i’ve got this humongous throbbing pimple on my forehead and it’s sooo embarrassing because everyone keeps pointing it out to me!! idk what to do it hurts to even wash my face. i’ve tried a face mask and stuff but it keeps getting bigger. i know it’s probably not the best but when i go to school i try to cover it with makeup bc it’s so bad. it’s raised off my face so much and is just so painful. the pictures don’t even do it a justice. help??