TW to those trying for a long time, please don't take offense i know this is not a long time to be trying just looking for advice.

So I have two kids who I managed to get pregnant with first month of trying! (5 &1 year old) So so blessed. We are now trying to conceive our third baby i am still breastfeeding our 1 year old daughter but my period has been back for 5 months now and I have been tracking it and its not regular like it used to be. I will get a positive OPK then my period 6-8 days later. We've been trying for the 5 months and haven't used any protection for the whole year (well after the 6 weeks of healing post birth) we knew we'd want another right after so didn't prevent it. I know many people have been trying for so long and I am in no way complaining or anything I'm just curious if my hormones are still regulating or what but why this is harder than the last two. I'm only 25. My husband is also 25.