I feel crazy

So you all are going to think I'm nuts but here goes. So we are TTC baby number 2 and I tested before my period and got negatives, cue period right on time. Fine whatever I'll try next month. Only this period is super weird, I have ZERO cramps and i always have bad cramping. I haven't really needed tampons or more than like 2 pads a day. My boobs feel huge and my nipples are itchy which normally I dont have any breast changes with my period. And I am nauseous, i have become a super smeller too like I can smell my LO diaper from like the next room (her poop isn't THAT smelly). I have terrible migraines every day the past two weeks, I get migraines but usually once a month expect for when I am pregnant-last time i had them every day. So me being the crazy person i am took a couple tests and negative which duh I'm on my period. So her is my nuts thought I had sex like 2 days before my period could I have somehow conceived before my period this is all just implantation or some other bleeding it's just too early to tell. (My mom said she had a "period" when she was pregnant)

What the heck is going on ladies????!!??