Help please

Okay so about 2 or 3 weeks ago , i took a pregnancy test and it was positive . A week later i took one and it was negative . I requested lab work suppose to go tomorrow but the past 4 days I’ve been bleeding and cramping up? I already got my period this month and not suppose to have it again till next month towards the middle of the month . Should i go to the ER ? Or just stay calm get the lab test and schedule an appointment with my obgyn ? We all know hospital bills are insane!