Blood test positive but no baby in Ultra sound..

So i had to go to the ER this morning for severe pains, I’m 5 weeks pregnant and haven’t been to my doctor yet, scheduled the 17th this month. They came back with positive urine and blood tests for pregnancy, so they sent me to ultra sound.. where the tech spent like 30 minutes pushing around taking pictures... no baby to be found. Said i either already miscarried(but I’ve had a absolutely no blood) Or it’s just to early to see the baby.. but my previous pregnancy i have ultrasound pictures from just 6 weeks... I’m so lost i don’t even know what to think? Had this happened to anyone else?