Please help. Period while pregnant.

Gracie

Ive been pregnant for 10 weeks. Had my first baby appointment last Friday, the nurse told me it would take about a week to get my blookdwork back, started bleeding heavily Sunday, they called me Monday saying I tested positive for a UTI and were sending antibiotics to CVS for me to take 3 times a day for 5 days. They seem annoyed with all my questions and assure me everythings fine but I've tried contacting the obygn bc it's Thursday and I'm still bleeding like period like blood. My next appointment is on the 30th. Please help, I'm scared bc this is my first baby and don't want to let my family and fiance down if this is a miscarriage.