welcome to HCM.
read your prob, high leval of HCG may present in germ celln trophoblastic tumor
, in ectopic pregnancy
, n in hydatiform mole or molar pregnancy. in case of molar pregnancy excrss vomit present n uaually misscarrige occur at 4or 5 month,
so you should get whole abdomen ultrasound
, n should rule rule out any tumor.
most probably this is due to molar pegnancy as your period started, in ectopic abdominal pain
you should discuss all these things to your doc n start proper treatment.