Took Morning After Pill, Period is months late

Patient: I had been taking birth control for almost 5 years continuously up until this past April when the Doctor at my clinic noticed that my blood pressure was dangerously high. I had just had sex that morning and had come into the clinic to get the next few packs of BC, but was refused them due to my high blood pressure. Worried, i asked for the emergency pill and took it right away. A few days later i experienced some unusual bleeding, almost like a period. My worry is that i haven’t had an actual period since then and am wondering if i am pregnant (it’s almost 5 months since that last time in April when i was taken off birth control, and was given the emergency pill). I’ve taken about 6 pregnancy tests, all negative! Another factor that i wonder about is that before going on birth control, i had very irregular periods…i’d skip months at a time, and even went a whole year without a period. I need some insight!