My body is really confusing me😩

My boyfriend & I are TTC for a few months now. I was on nexplanon implant birth control from 2014-2017. I still have the “expired” implant in now, didn’t have the insurance to get it taken out which I can now do. So the implant “expired” December 2017. Around June 2018 my cycle decided to come back, as it completely disappeared once I started the nexplanon. Since June 2018 my cycle hadn’t been regular. Some months I would get my period, some months I wouldn’t. Around February 2019 it started to become a little more regular but as a 35+ day cycle. In March this year, my boyfriend & I wanted to start TTC so I started to track ovulation. I normally get a peak test CD 10-12. I have been ovulating CD 13-15. This month was a little different. I got a peak test 2 days in a row, CD 10 & CD 11, the following day, CD 12, it was high, 2 days later, CD 14, it was peak again. I hadn’t noticed any ovulation symptoms except SLIGHT cramping. On CD 21 I had left ovary pain & uterine cramping. I didn’t test for ovulation. I figured this might be ovulation time being that during the peak & high tests I didn’t feel any ovary pain. My boyfriend & I have DTD 6 times from CD 7-CD 24 because we weren’t sure when exactly I ovulated being that the test went from peak to high & then back to peak. Has that ever happened to anyone before? I’m just trying to figure out when I ovulated so i know whether there really is a chance of a BFP. From CD 21- today which is CD 33 I’ve had lower backaches every day, some gas, hiccups, a slightly sore throat, headaches almost everyday, & fatigue. I was “supposed” to get AF 3 days ago but my periods are rarely ever regular. I took a test 2 days ago at night & it was negative. I took a test yesterday morning & it was negative. Last night & this morning I had light pink spotting. I know this was a lot to read & im sorry I’m just all confused & really want nothing more then to surprise my boyfriend with a BFP. Also wondering if the “expired” implant in my arm is causing infertility. If anyone can share if they’ve had similar symptoms or the same experience of a peak, high then peak again from a test I’d appreciate it. Thank you!