Tattoo what to expect?

ok im not new to the tattoo scene ive got loads full sleeve ,legs and back ,what im asking is im getting a aztec tattoo at the top of chest going down to about my belly on like a rectangle with a design in it,anyway i spoke with the artist he reckons 2-3 hours straight and its going to hurt lol im scared ,has anyone had it done there and does it hurt that bad?none of my other did except on the wrist a little.