Should i worry??

Im 9 weeks pregnant. My 1st baby. Scheduled for ultra sound in a week. Im a server at a restraunt and yesterday night i picked up this large tray full of dishes. I made it three steps and sat it back down and asked someone else to carry it for me, because i realized what i was doing was too much on my body. So, with small cramps in my stomache i went in the ladies rest room. And i spotted red blood in my panties. I just want this baby to be ok. Does everyone think im ok?