First period came

I had my first post partum period 28 days ago and I am still breastfeeding 3 times a day. I put 28 days by default but I don’t know how long my cycles are. They were 25-30 days long pre pregnancy.

We did have sex around ovulation time and I took a test at 9 DPO which came back negative. I don’t normally test that early but I bought a Perifit and it says you can’t use whilst pregnant so I tested just in case.

I think the chances of me getting pregnant that fast are extremely low but I am scared to test again as I know I will be a little disappointed if it’s negative. However the longer I wait and have no periods the more I am going to hope… and then get disappointed if I just happen to have irregular periods.

Has anyone gone through this?