Uti or something else?

So It's 4am, i woke up at 330am with the insane urge to pee. I peed and it was super dark and burned. I'm now back in bed and it still burns. I've been CHUGGING water like crazy (all day before this happened), i peed right before going to sleep at 1130. I am 36+5. I don't understand why it's all of a sudden burning so bad when I've done nothing to cause a uti?