Confused partner use protection but could i be pregnant?

[Carr1978]

I had a missed miscarriage, found out at 12 week scan that my baby passed away at 7 weeks, after that my partner said no to anymore as as we both work and I'm 41 and got 6 kids already, so he uses protection every time now, I've had one period since and second wasn't even a period sorry for tmi but it was brown and only for few days when normally lasts 5 days, i know it might sound mad me asking but could there be a chance I'm pregnant, i took a test a day after i finished spotting but was negative, confused any input would be grateful thanks.

It could have been implantation bleeding so if you tested the day after spotting had finished there wouldn’t be enough hCG to be detectable by a test. Take another test once it’s been a week since you finished spotting.

Thank you for your reply, I'm trying to hold of for a week, I've brought 2 more test so just waiting to take them, I'm thinking maybe what we used as protection could of split or something, not sure but would be very much wanted if I was.