I Like to Workout

Well I do, but today was my first time working out since a year ago. I was injured in football last season so I couldn't work out. This gym that I go to opened up a few days ago and it's really nice, but WOW am I out of shape/weak. I'm actually kinda embarrassed and mad about it even because what was the smallest amount of weights put BIG work to me. I'm 5'11 and 160 lbs, and the fact that 20 reps with the 45 lb bar wasn't easy? Makes me worried. I was able to max at 145 last year, now I doubt I can even do 125. Maybe it is because it was my first day. My friend and I plan to go there 6 times a week for who knows how long. Hopefully I get those gains overtime!!! It was a 2.5 hour workout by the way. Both upper and lower body (and a bit of core).