I have swelling on my upper lip. what should i do?

Examination: Assuming it isn't from an obvious cause involving trauma, the only safe bet is to get it looked at. If it is from trauma, treat it topically with cold packs and see if it resolves in a few days. If it fails to do so, have that exam to be sure. If it is of viral origin, you could be contagious if it opens up to be an exposed sore, so be cautious about salivary contact with others.