Postpartum Period

I had my 4th baby about 3 months ago. Healthy baby and easy pregnancy with no complications. After my first 3 pregnancies I was always on Mirena at my postpartum visit it was placed until my husband and I decided to have more. With this being our last my husband and I decided he would get a vasectomy and I would not have to go back on birth control, my doctor was fine with that idea.

Now, last month I thought I got my period it was extremely light and only lasted 3 days. I still logged it and it said my next period would be about 5 days ago. I took 3 pregnancy tests all negative. My husband and I are using protection until his vasectomy in October (soonest we could get it scheduled 🤦🏼‍♀️). My doctor wants me to test again in a week. I’m having cramps and it feels like I have my period but no blood.

I am only formula feeding since my daughter was born.

My question is how long did it take for other mommies periods to return after postpartum? I know 1-3 is normal but I know that’s not always the case.

Just trying to ease my mind Incase the doctor says #5 is on the way 😳