3 days late

Trying to be patient and wait to test while staying super healthy and drinking plenty of water. 
3 days late, no sign of AF other than sore chest. It's a different kinda sore though. Like deeper than usual. Clear/milky discharge. Constant dry throat. And mood swings, Holy hell.
Should I just give in and test?? I'm so terrified of seeing a negative.. 😞 but I really, really think this might be it..