I need some advice

okay here it is. I was supposed Ronstadt my period on the 10th. today is the 15th. I'm 5 days late. and no sign of getting it either. but this morning I threw up and I have really really sore nipples since last night. could it be just stress? or periods just late and coming soon? I've got fatigue,sore boob's, nausea, mild cramping, and my body aches as well as headaches. think I'm pregnant and should test? or wait and see if I get my period? I'm new to the site and haven't posted much. I'm newly engaged and I'm almost 20. and yes we are trying! TIA.