I can't poop even thou i been really gy these last 3 days.?

I tried this morning, afternoon and just now and nothing...not even a single log. I however been really gey the last 2 days. I also have the cold/flu and i dunno if that might be a reason due to lack of energy. I tried eating 2 scopps of raisin bran cereal but i just vomited it. what can i do for pooping?