Ok well first of all, to get high, you need to not only hold the smoke in your mouth...once you inhale, INHALE A SECOND TIME with a deeper breath to actually bring it into your lungs...sounds alot worse than it is. NOW, you might get a littttle freaked ur first time high. Basically you kinda find yourself spacing out on random things without realizing it. After a few seconds, youre like "wow, i just looked at that soda can for 20 seconds" and then you laugh...and youll be hungry. Food tastes reallyly good, and different songs will just "feel right" to you, haha.
Its tough to explain, but give yourself a good 3+ hrs to fully come down. Most of all, relax about it, it won't last forever, so try to enjoy it.