I get a lot of swelling and pain around my mosquito bites. Like it will make my whole knee hurt if I'm bitten there.

There are varying degrees of allergic reaction to mosquito bites, and it sounds like you qualify as having a true allergy. Aside from taking anti histamines, you can use the usual chemical repellents, or try some of the home brews that are all over the internet (lavender oil, lemon juice, vanilla, etc).

Listerine, in a sprayer, works well to deter mosquitoes.