More than the flu??? TMI!!

Soo two days ago, I was throwing up and couldn’t eat anything without it throwing up. I went to my doctor and she said it’s just the flu and to try and take gravol or other medication for the nausea. I stopped throwing up but now my pee is a brownish/reddish colour? It depends on the time ! This morning it looked like straight blood not pee. But it’s closer to night time and it has a brownish tint? What could this be????