How soon to test

Katie • Stay at home mommy as of 6/30/16!!!
Is it too early to test?? Period due 21st so 6 days.....part of me wants to test and part of me doesn't. Would I see results or not?? I'm nervous. i've had a nasty Bellyache yesteday which is weird because I don't normally have this feeling before my period. Had cramps last week but those went away after a few days. And todsy feel better but I feel different in my stomach. Hmmmmmmm oh and not to mention last month my period came five/6 days early and nothing yet!