Does having intercourse during implantation boost chances to get pregnant?

I had IUI on Sunday and that's when my egg has gotten big enough (23mm with thick lining). Our doctor suggested to have intercourse two days before, which we did. I felt light cramp, bloated, and exhausted after IUI; but that only lasted for 2 days and now I'm back on my game and no longer feeling all those symptoms.

Today is day 5 post IUI, which we learned the implantation period. My husband was out of town right after IUI; hence we were unable to have intercourse and will make it up for it during this implantation period. Will that boost the chances to get pregnant or is it too late?

Also, is it normal not to feel anything after IUI, even when I take progesteron and metformin? I am afraid that IUI does not work this time because I feel ok.