13 days late and no AF

Currently 13 days late with no signs of AF. I’ve had nausea, migraines, exhaustion more than normal and forgetfulness. I talked to my OB about being this late and requested a blood test since FRER tests show negative. She told me she’d give me a prescription for Provera to induce a period. I’m just so confused as what to do! Should I just take it or should I wait it out? I don’t want to risk a MC because I thought I wasn’t pregnant but I also don’t want to wait to long either!