I don't know if this is the place or not but I need help.

My husband and I have been fighting badly.

This morning I wake up and found cum inside me, he said he did it in his sleep but idk, I know you can get pregnant at any time. Our little one isn't even 4 months old.

How soon until I can take a test? I can't take plan b because don't have the money. Just please help i can't get pregnant again this soon

Edit I am on birth control but my body doesn't respond well in the first couple of months, and I didn't just "magically find it", it's pretty obvious what it was when you wake up, underwear off, and you know what fun feels like and you know what wiping it away when going to the bathroom is like from back when you we're TTC.

Also last night I took a sleeping pill because I've been battling a migraine and was trying to sleep it off.