Never normal. Please contact your gyn.
Is it normal for my girlfriend to bleed after sex during her first trimester, she is 7 weeks. Would this cause any sort of problem for her or the baby?
Bleeding. Bleeding can certainly happen and doesn't necessarily mean anything is wrong with the baby. Spotting can be typical but shouldn't be as much as a period. If large amounts of blood, bleeding often, or cramping, get evaluated now. Would discuss with OB to see if she needs to get checked sooner.