Ok so I have a 3 month old that is exclusively breastfed . Me and hubby haven't been using birth control. (Yes I know there is a chance you can get pregnant while breastfeeding but you can somewhat use it as a method of birth control as long as certain criteria are met . )  That being said on top of the breastfeeding he does "pull out" just in case . ( yes I know that pulling out is not a super effective method) 

So my question is if I am 3 months postpartum and haven't yet had a period ( not sure if I could be ovulating though) and I am exclusively breastfeeding and when we do engage in sex hubby pulls out .. What it still be easy to get pregnant or more of a slim chance ? Reason why I ask is bc he other day I noticed some brown spotting and I have read it could either be my period trying to return or implantation bleeding .