Preparing myself for the worst - Pregnancy test getting weaker / ?dropping HCG levels

[AmyMaria2015]

Hi, long time reader, first time poster.
I suspect that I am going to have a miscarriage.

Background: Came off pill on 5th May. Pretty certain I conceived on 11th May (based on CM). Bleeding for 4 days from 22nd - 26th May, then a BFP on the Wednesday 5th June! 😱❤️
Based on the info I have, I suspect I am currently 6-7weeks pregnant (i.e. 4-5weeks from conception). Please correct me if this sounds wrong!

Purely out of curiosity, I did another test on the Sunday (9th). The preg. line took a lot longer to appear and was a good bit weaker.

I then was poorly on Monday night/Tuesday morning, so I went to the Drs on Tuesday. They took my bloods and the HCG levels were 550. I went in again on Friday and was tested again.

So here we are, Sunday night. Tomorrow I'll get the results and I'll find out (hopefully) if the pregnancy is viable or if I'm heading towards miscarriage. Obviously I am very nervous about it.
As recommended by Dr, I waited a week since the last time I took a test. I took another one today and I feel like it was weaker again.

All tests taken were the same brand etc. so not much scope for different levels in different brands, etc. Although I have to admit I was surprised that my HCG levels were 'so high' considering the test line looked so weak!

Has anyone been through this?
If so, what usually happened? What can I expect if I get the news that the levels have dropped tomorrow?

I'm also terrified that the pregnancy is ectopic 😅 I have no reason really to think it is - it's just something that comes up a lot when you Google 'weaker pregnancy test/ dropping HCG levels' 😅😅🤷🙈

Please help - I'm nervous as Hell and need some facts to help prepare myself!

Thanks in advance xx

Lack of line progression 4-6 weeks would indicate a pregnancy which is not viable (always been the case for me) however after 6 weeks hcg levels plateau and change as the placenta takes over so they become less reliable later on in pregnancy?

I've had an ectopic and lack of line progression isn't always the case - my hcg was doubling perfectly and had really strong positive lines - it's ones sided pain you should be aware of in an ectopic situation x

@itwasalovelydreamwhileitlasted Thank you for this. I'm going to be ringing my Dr shortly.
Have you had a line that got weaker? If so, what happened? Did you start to bleed on your own, or did you need medical intervention?

Thank you for taking the time to comment xx

Update: I rang my Dr and they say my HCG levels are "rising in line with pregnancy".
But my levels on Friday were only 775? And my levels from Tuesdays reading was 550. My understanding was that levels should double every 48 hours, so to have a 50% rise in levels over 72 hours is disappointing.

I also started lightly spotting about half an hour ago. So it does indeed look like a miscarriage...