Burning? Guys help!

Every time my boyfriend and I have sex it burns during and after for about 10 minutes then goes away. Ive been tested for infections and nothing. I’m on birth control so I was thinking maybe vaginal dryness? But we use a water based lube, so id be confused if that was it. Also the birth control makes me have literally zero sex drive and I dread having sex.. so maybe being uncomfortable and not relaxed is causing it too? Things are going downhill because we don’t have sex and we don’t have it because I cant enjoy it.