Positive test 2 min after period, chemical pregnancy

I had two days of tri-phasic, elevated BBT, which has only ever happened before during the cycle I fell pregnant with my son. I was honestly a little surprised when my tests were negative the last two days because of it. This morning, day of my expected period, the temp dropped back down below baseline, so I knew it was likely to start. I took a test this morning anyway, with an FRER, thinking the negative test would confirm it for me and make the period starting a little easier, which I've done in the past. Peed on the stick, set it behind me. Wiped, and had tiny pink tinged toilet paper. Realized I'd started my period (confirmed later with medium flow red). Checked the pregnancy test, only to see a super faint line. I realized it must have been a chemical pregnancy, and was surprised how little it affected me, likely because I knew before hand the period was going to start today.

Well this evening, after a very, very long day, it started to hit me a little more. I wish I hadn't taken the test this morning, because then I never would known. Now I'm mourning what could have been. I didn't ever even have the moment of thinking I was actually pregnant this cycle, knew from before the test that my period had already come, but it still hurts a little. We only decided the day after ovulation this cycle to start trying, so I wasn't expecting a pregnancy, and having it almost happen is painful. I don't anticipate difficulty getting pregnant again, but it's still a rough way to start my TTC journey for my second child.