Obviusly symptoms and conditions

I'm freaking out!!!!!!!!! SOMEBODY WITH THE SAME SIDE EFFECT PLEASE HELP ME....I was on YAZ since the summer and it sucked cuz I'd get my PD every 2 weeks....i finished my last pack on November, took December off and towards the end of the month i had unprotected sex so i had to take the PLAN B pills and three days later i got my pd. so everything seemed O.K.....theeeen i started on this jump off LOESTRIN PILL. I was supposed to have "protected" sex for the first month but towards the end of the month (when i was NOT supposed to be ovulating) i had unprotected sex and i haven't had my PD. for 2 months now....Last month i did a pregnancy test and it came out negative....I don't really have any "early pregnancy" signs....i feel fine but CAN ANYONE LET ME KNOW IF MISSING A PERIOD IS NORMAL? I'm just thinking that switching from a different birth control pill and taking the plan B pills might have messed up my cycle. Thanx.