Is there something wrong with me? Should I see a doctor?

So first of all, throughout all of December my period didn't come, and suddenly comes in January the 8th. My boyfriend and I had sex around January 15 and I ended up taking plan B. Now I suddenly get my period, again, and it heavier and it smells a bit different.

It's been 4 days and I still have my period but its way lighter than before and this morning I woke up and felt horrible. My body was aching (still is) felt the need to puke(not pregnant though), throat hurts, warm air coming out of my nose and ears (at least that's what it feels like), runny nose, and my whole body is weak. Are these the Plan B side effects or something different? Please help.