I'm eight days late on my period and the only symptoms I have is tired and nasua.

Have you taken an HPT yet? If not, this would be a good time to take one.

I'd also like to point out that you usually do not feel pregnancy symptoms immediately. Your first symptom of pregnancy is the missed period.

Take an HPT with first morning urine.

Any extra stress going on? I'd go with the above, first morning urine HPT.