Scared of sex

I'm 3 weeks pp and read on here about some women who have already at 3 weeks had sex. This has blown my mind! I feel awful now!

I had a natural birth and only a first degree tear (no stitches) but still I can't think of anything more scary than having sex now. It all feels fragile still- and my stomach is like a wobbly jelly and my hair is full of baby sick and I'm sleep deprived - I mean really- how do people do it?!

I know I should compare myself to others but I feel quite inadequate and deflated now!