I had a MC before I had Sophie. It obviously varies from person to person. I felt safer after 12 week scan, but still nervous. I think it's natural. Don't beat yourself up over it, allow yourself to feel it, it's normal, but try not to let it take over.
I only say this, with well meaning, as a good friend of mine MC twins at 8 weeks, she then got PG straight away again, and basically, by her own admission, didn't enjoy her pregnancy at all. She actually developed pre natal depression. She was a wreck. She said she just couldn't relax until baby was born, which she was, very healthily, in July last year. She (friend) is fine now.
What was a definite comfort to me, was knowing how very very common it is, and that it didn't mean that because I'd had one MC I would have more, IYSWIM.
I think there is a thread on here for pg after MC that I went on when I was pg with DD2. It should still be around....
Thinking of you, and sending lots of healthy vibes to babyLFS.
LM xxx