Girl Problems - looking for advice

Don’t really know what to do. Me and my mum don’t really talk and I’m not comfortable talking about girl problems with my dad. So hopefully all you beauts can hopefully help me.

From around 5 this morning I’ve had really bad urges to go to the toilet constantly. And when I go hardly anything comes out. But now I’ve drank about 3-5 litres of water when I pee blood clots are dropping into the toilet bowl and I have pain when peeing. I came off my period yesterday and my flow at the end was really light. I don’t know why this is and I know it’s not a urine infection as this is like nothing I’ve ever had before.

Please help??🤷‍♀️ x