Af 4 days late, possible tmi

Period was supposed to arrive the 27th and is no where in side. My cycles are messed up since my surgery in October (gallbladder), and I thought I ovulated in the 15th but could have possibly ovulated later? Having bad back pain, nipples feel like they are on fire and boobs feel heavy, some pinkish discharge only when I wipe, cramping and little nausea. Negative tests for the last 3 days. Could I possibly have ovulated later and this is implantation bleeding? Just need a little insight! Baby danced a lot this month to.

Thank ladies

Side note: baby danced last night and was a little sore down there. Felt like cervix was low because I swear he kept touching it.