Pregnancy scare, EC, no periods.

I took ECP a week after the onset of this cycle, after having unprotected sex that day. Then I had some irregular bleeding for 3 days, which started 5 days after the ECP was taken. My cycle is mostly of around 28 days with some occasional 25 to 30/31 days. My periods has not yet started, and currently it is the 31st day of the cycle, so when should I expect my periods. It has already been 3 weeks since I took EC, and internet says we should expect periods within 3 weeks. Will the irregular bleeding be considered a new cycle, will i get periods later because of it. Also, MTP can be doNe only 7 weeks of gestation, and because it is considered from the beginning of last cycle, will it be too late because this is already the 5th week then. What is my best option right now. Also, can beta HCG be done without prescription?