I have what looks like an abscess on the inside of my cheek. theres no pain in my gums or teeth. or pus coming from the abscess. what should i do?

See your dentist: See your dentist.....it could be simple cheek trauma or a blocked salivary duct but it would be a safe thing to have checked out.

Abscess: If there is an abscess, it means there is an infection. Not quite sure what you mean by "looks like an abscess", but if has not resolved on it's own in a few days then you should see your dentist for an examination.