Long post.. I just feel like I have so many Q’s

So this is probably gonna be long and ranty but if you read it all and have any advice I appreciate you I just don’t have anyone to talk to. Anyways, me and my SO have been together for 3 years. We are engaged are wanting to start TTC now because 1. We REALLY want a baby! And 2. Because we know it can take a while. So I used to have the nexplanon but I had it taken out in July 2016. My doctor said it could take a while for my cycle to regulate but I didn’t get my first “period” until May of 2017. I had it for two months pretty heavy and then NOTHING. So I went back to my doctor on November 28th,2017 and I told her what was going on and that me and my SO are wanting to TTC and so she put me on Provera to try and get a “withdrawal bleed” and she put me on a prenatal. And finally on the 18th of this month(December) I got a period. It lasted until the 26th. And I have been logging on this app since the beginning of this month. So it says my fertile window started the 27th and I am suppose to ovulate on the 1st. I don’t have enough money this month to buy any ovulation tests so I can’t really confirm it. And my doctor also said just because I bled doesn’t mean I’ll ovulate this month. So really I’ve just been reading everything people post on here and researching stuff about the female body and this kind of stuff trying to learn more about it. My next period is suppose to be on the 15th of january. But my and my SO have had sex every other day since I stopped my period. I guess I’m just gonna cross my fingers and hope my period doesn’t come next month?? Idk HELP PLEASE?:/