Could be pregnant or?... Please help.

So normally my period is very regular. It's always around the same time every month maybe a day or two early or late but I'm like 5 or 6 days late this month and today I haven't felt so hot I was dizzy and nauseous this morning and I've been tired lately. me and my SO aren't ttc but we aren't trying to prevent it either. I haven't taken a test yet I'm kinda just waiting to see if it starts soon. Could I be pregnant? Please no negative comments.