Hi so ive had cold sores before but havent in a while, my lips were dry and i put chapstick on then they swelled up little blisters everywhere?

Maybe allergic: By the history this sounds like an allergic reaction to the lip balm. However, do you feel the same symptoms (burning, tingling or pain) that you feel when you get your cold sores? If you can't tell, then it would be best to go see a dermatologist who can make the diagnosis usually by seeing the lesions. The Dr. may have to perform a viral culture to be sure. A culture is not painful.