Might be pregnant again?

Hey guys I gave birth to my Daughter July 29th and I had my period right on the 7th of September I was waiting for my period to come back and it hasn’t after the first time. I am 16 days late and I did test but it was a few weeks ago but I’m also breastfeeding and my milk supply has gone down. I have the white discharge which is the same discharge I got the first time I was pregnant I’m really nervous and don’t know when I should test again. Please give me some advice on what to do thanks