See your doctor. At 34 weeks there are several possible causes of abdominal or pelvic pain; most are not serious but one must get more information to determine this. As long as the baby is active, and there is no vaginal bleeding, regular contractions, or amniotic fluid leak, then it is unlikely to be a problem. To be safe, one should be checked by the doctor/midwife and possibly be put on the fetal monitor.
See Dr. Sharp pains in the pelvic area when pregnant require your dr. To examine you, call your ob/gyn now. Good luck.