Yesterday after a full day at work, ate like shit and lack of rest I went to the gym as it is my daily routine. Got to the gym with the ol lady and began chest day, typically we work out seperate but yesterday I wanted to spend time with her and catch up on some current events. We started on the flat bench, her warm up was with 90lbs so instead of taking the 25s of I decided to strech with the 90 and warm up with about 25 reps but more stretching. She moved up to 135 and knocked out 10 so I did that as well and then she went up to 165 and repped that for 8. By that time she was done and i was just slinging around 5lbs in each hand for the 15 minutes she was doing that. My mistake came when I said skip the warm up and just get into it so I could move on with her, i pressed 225 for 15, jumped to 315 for 10, 405 for 8 then 455 for 3, on the 3rd rep of 455 while pressing up, about half way up I felt pop corn and excruciating pain in my right peck, I imediatley lost all strength and the 455 dropped, my spotter held it until i could shimmy underneath and dropped it. I grabbed her and went straight to the ER, at the ER they gave me a shot of toridol, put me in a sling and said to ice it. Woke up this morning and the right side of my right peck, armpit and bicep is black and blue. I have an appointment tomorrow for an MRI to see whats tore. I can raise my arm with pain so i dont think anything exploded or tore from the bone. Needless to say, dont skip your warm ups gents. This is my first injury in the 13 years of heavy lifting and im a little depressed.