I did barbell bench press for the first time yesterday. I usually use two-40lb dumbbells. The guy who was spotting for me loaded up the weights on the barbell (I didn't think to look to see how much) and I did 18 reps. He asked me if I wanted more weight, said "sure", and he put more on without telling me (and I didn't think to ask) how much he'd gone up to. The weight was definitely heavier and I was only able to do 8 reps. Decided that was enough and asked him how much was on the bar, he told me 135lbs. I looked and sure enough, it was 135lbs. I've never lifted that much in free weights before. Absolutely amazing to me that I can barbell bench press 135lbs for 8 reps the very first day I tried.
I do have a question about form. Is my back supposed to be flat against the bench or am I supposed to have my chest up (i.e. balancing on my shoulder blades)?