What Causes Prolonged Heavy Periods And Abdominal Pain After Taking Levonelle?

i had unprotected sex with my partner a month ago in the middle of my cycle and took the levonelle morning after pill a day later. i have since started my period a bit late and very heavy and i am still bleeding 10days later with some abdominal pain in the lower right side. i have also experienced sickness for the last 3 and a half weeks. should i have any concerns or is this normal? i am concerned about things such as eptopic pregnancy and miscarriage and was wondering if there is ayway i could find out so i know i will not experience problems conceiving in the future.