Does anybody know what this means,

So today I woke up feeling sick, lots of cramping, sore boobs and when I went to the toilet there was a bit of discharge that looked like it had a bit of blood in it.......my period was 16 days ago, I am ttc, I BD on Sunday night and Monday night(nothing before then) ...according to glow I should have Ovulated yesterday however I think I ovulated early either Sunday or Monday...so I am at most 3Dpo

This is exactly how I felt last time I was pregnant but this didn’t happen till a lot later....surely 3Dpo is far to early to be getting any symptoms?