I had un protected sex 4 days before my period!
If there's a chance I'm pregnant will I miss this period in 4 days? Or miss the next period the following month?

It is very possible that you will still have a period in four days, Wait until next month before you stress yourself out.

It is possible to still have your period in four days, very possible I was 2 months pregnant before I missed my period hah I had no idea.

Having this period does not mean you are not pregnant, so you can stay stressed for another month