Plan b

I had sex Sunday the 17th and took a plan b the following Wednesday. That Friday or the Friday after that (I can't remember..) I bled a little. It was an awkward color like kinda pink and kinda darkish brown but it wasn't a lot. When I wiped once it was there and again then it wasn't and I peed, wasn't there then the next day I peed and it dripped out but then wasn't there after I wiped and hadn't been back since so about 1 day of off and on. I had unprotected sex again the next Monday and he came in me but I didn't take another plan b. Now I feel my boobs are becoming sore, nipples itch occasionally  and I feel kinda nasty when I eat certain types of food, like sweet food makes my stomach feel gross and I've been feeling like "baby barfing" but won't actually do it. This Saturday I was constipated.  Now it's 3 weeks after I took the plan b. What I'm wondering is was that my "period" that the pill was supposed to give me or was that something else? Ik you can't give me a straight answer so I guess any thoughts? I'm not ttc but if it happens, we don't mind. That's why no condom was used.