Squirting or pee? ๐Ÿ™ˆ๐Ÿ’ฆ

Ok so whenever I have sex with my boyfriend and it starts to feel really good I feel like there is this tension building up in me. Like I need to pee or else I will explode. But it's only ever when we actually have sex. When I orgasm by masturbating I never have this feeling it's only ever by penetration? ๐Ÿ˜
Is this normal or do I actually need to pee? ๐Ÿ˜‚ I always try to fight that feeling because I don't know what to do. I want to release it but I don't know how? ๐Ÿ˜ฉ