Light brown/ pink blood like period while 5 weeks pregnant is that normal should i worry?

HCG: This is probably old blood and some scant breakthrough bleeding; however, I would suggest a repear serum HCG test for pregnancy.

See a Specialist: Please see your obstetrician soon. This is normal in 85% of the cases. In the rest, it may be associated with miscarriage or an abnormal ectopic pregnancy. You will need some blood tests and ultrasound. Good Luck!