I had protected sex by using a condom, however, when exiting the condom fell off...the opening was still on the outside and I wasn't aware until he had made me aware. I was concerned and purchased Next Choice and took it 48 hours afterwards. I was on birth control 2-3 months before this instance but was experiencing extreme joint pain, flushing, and slight shortness of breath. I took the first dose at 2 P.M. and currently am experiencing slight shortness of breath. I am scheduled to take the 2nd pill at 2 in the morning. Should I cancel this because this is a sign of allergic reaction? Would the 1 pill be effective enough or without taking the 2nd dosage it would not work?