Bleeding in pg is very very scary (serial bleeder here) BUT it's incredibly common (something like 1 in 4 women according to my mw) - esp in early pg. Huge increase in blood to the cervix in pg makes bleeding much more likely. Small amounts of light bleeding (esp if not bright red)= best possible way to bleed
Fwiw, with ds I bled throughout my pg - usually 2/3 times a week. All shades of blood, and some little clots (sorry if tmi) He is now 4.5 - came 4 weeks early but otherwise as normal as any other 4.5 yo boy..... I also bled with dd, but less.
Obviously, mc is more common than most of us would like to think, but unexplained pg bleeding is too.
Suspect you'll have a transvaginal scan. Like a huge dildo ... but at least you don't have to have a full bladder...
Try & relax - nothing you can do other than take it easy.