Possibly Ectopic, need advice

Just want to preface this with that I’ve seen my doctor and am under her care.

Its a bit of a story so thanks for reading! I got my regular period July 20 as normal. I believe I ovulated early to mid August and husband and I TTC so we were intimate although I’m not sure of the exact day. I took a pregnancy test Aug 18 and it was definitely negative. I had my regular period the next day. Normal flow, normal length of days, normal cramps and everything. About 3 days after my period ended I start getting brown spotting. I chalk it up to that weird brown blood you sometimes get at the end of your period…but I’m also getting those little twinges in my vagina I sometimes get before my period starts. The next day the spotting continues. The following day it’s red and heavier so I worry it’s this fennel tea I drank causing break through bleeding. I do have sore breasts at this time and a friend asks if I could be pregnant? I take a test and BAM, pregnant! Two more at-home urinary pregnancy tests turn positive, I am so confused! Especially since I had a negative pregnancy test Aug 18 and then my normal period after. I think perhaps I’m having a chemical pregnancy and miscarriage, but am cramping. I decide to go to ER on Sunday, 8/29. My bloodwork comes back positive for pregnant, Hcg is 505. They cannot see the embryo or sac on the ultrasound (I had abdominal and vaginal). They see an unremarkable cyst on my left ovary. The think I’m miscarrying and send me to follow up with OB-GYN. On 9/1 I get bloodwork and Hcg is now 685, so not doubling as it should. I get bloodwork again on 9/3 and Hcg was around 1200. Since I’m still having cramping and bleeding on 9/7, OB-GYN advises me to go back to hospital for possible ectopic. My Hcg is now 2100 (still not doubling). There is still no sign of embryo on ultrasound and they suspect ectopic. They’re not sure if the cyst is the pregnancy but they don’t think so, yet they’re so confused they can’t find the pregnancy. I do follow up bloodwork today 9/8 and Hcg is 2,444. The doctor thinks I should take the shot to end it as they think it’s ectopic and unviable. When I ask about the bleeding they say well that does make us think you may have an intrauterine pregnancy, we’re not sure. So I am at this stage. I just don’t want to be off with my dates and the baby was not yet big enough to be seen in the uterus. I think the bleeding is concerning and the fact they can’t see it. I’m def going to follow my doctors care plans but wanted to vent/get advise. Thank you all <3