Af cycle and breast feeding

So, I’m currently 3 1/2 weeks postpartum and freaking. Yesterday I got a call from my doctor saying she didn’t want to do birth control until I started my period due to complications with bc in the past. I’m exclusively breastfeeding, and I heard some women don’t get their period until they are completely finished with bf. Is there any way to track if I’ve ovulated without starting a period if my lh is constantly elevated and I get multiple peaks a month? bbt only shows if you have already ovulated, so that’s not super reliable in my situation.

Also I can’t use condoms as I’m allergic to every kind I’ve tried, latex, and no latex. I was planning on waiting to do funny business after the first month on bc, but now that I may have to wait until my son weans, I really don’t want to make my fiancé wait, especially since our wedding is in two months.