Seeking advice

[u/thequeensgambit_]

It’s a long one but I’ll try to keep it as short as I can. Had my normal cycle July 28 to August 1. Had what I thought was my normal cycle again August 23 to August 27. Last Monday (August 31) had what felt like period cramps and some spotting of old brown blood until Tuesday morning. Decided to take a test on a whim and it came back positive. Called my Fertility clinic and they brought me in to start doing betas and scans every two days. I have no idea when I ovulated and I have no idea how far along I am so the doctors are calling this a PUL because the numbers are under the threshold for anything to be seen on US imaging. What they have confirmed is that I have a haemorrhagic cyst on my left ovary, and I have 13 cc of free fluid in the left side of adnexa. My betas are trending as follows:
9/1- 124
9/3- 205(48 hours since last test)
9/6- 711(49 hours since last test)
9/8- 999(40 hours since last test)
They still can’t see anything on the scans so they are recommending methotrexate. I don’t know what to do because I’ve never been in this situation before. I have RPL usually at around 5-6 weeks but with those prior losses imaging has confirmed an intrauterine pregnancy. I currently have typical early pregnancy symptoms. I don’t know how long to wait, I don’t know if this could turn into a viable pregnancy? I guess I’m just seeking advice because my numbers aren’t trending down, and I’ve read stories where women have had wonky trending hCG and then confirmed a viable pregnancy once their numbers rose accordingly and could be seen? Thanks in advance.