Faint Positives, NEGATIVE HCG Blood Test

Hey all, I wanted to ask a question with some background info and see if anyone else has had this happen!

For starters, my SO had a vasectomy 9 years ago before we met. Im not sure if somehow that has anything to do with it BUT hes 100% the dad lol anyways, I started having very distinct/specific pregnancy symptoms on 6/10/22. Things that I only experienced with my 1st pregnancy. Spotting, psoriasis breakout, and consuming alcohol well enough to be intoxicated but not feeling even the slightest effect (the opposite reaction most people have typically when drinking and not knowing they are pregnant) All 3 of those symptoms I've never had before outside of pregnancy. So I test on 6/11/22. Faint positive. The next 4 days I continue testing once/2x per day to make sure it wasn't a false positive because again SO had a vasectomy. All faint positives after 2-3 minutes. So I immediately believe that im pregnant and its just too early for it to be a dark result. I would've been 3/3.5 weeks. On 6/15 at 1am and 7am I tested, again faints but more visible than the rest. At 1pm I had an hcg blood test, it was negative. The minimum value for 3 weeks is 5. My value was 0.50. Im still testing positive at home, still faint. Im supposed to start my period 6/21/22 and was told if I do not to come back in for hcg re-test.

For reference my 1st pregnancy I found out via home test at 5weeks and it was dark positive immediately.

My OB/GYN's nurse told me that before starting your period, there is a surge in hcg which could be causing my at home positives. Im confused by that though because urine tests require a higher concentration of hcg to even test positive compared to blood tests, yet my urine tests are positive and the blood test was not. And also I've had pregnancy scares before and tested 6 days before/closer to my period was due and been completely negative (meaning I didn't get a faint + even with the supposed hcg surge, so why would I be now?)

Im also using different brand tests as well so its not just a bad batch/ lot number from the company.

Sorry this was so long, im just confused as can be and wondered if anyone else had similar events happen!

Thanks is advance!