Last period finished 11 of april , had protected sex , cramps and low bk pain pregnant or period arriving ? no other symptoms , super stressed

Could be either: do a home preg test. if negative, wait it out.

Low back pain: Low back pain, abdominal/pelivc cramps can be a symptoms of conditions such as pregnancy, urinary tract infection, vaginal and pelvic infections, intraabdominal condiitons such as ovarian cysts. If a patient has these symptoms, they need a medical evaluation. A physical exam and lab tests may be required.