Does Delayed Period, Breathlessness And Sickness Indicate Pregnancy?

im 16 and since last week ive been feeling sick .. ive been hoding down vomit and having shortness of breath and bad headaches when i hear noise . ive also been having cramps but my period doesnt come on until the end of the month. & when i eat i feel like throwing it all up .. i have no idea whats wrong with me ...a friend says it could be pregnacy but i dont know ... help.?