Sounds fine to me.. In general that's not a bad amount of time i wouldn't think. It really depends on your experience and what you're lifting though. When i started out, my workouts were quite lengthy.. It seemed the more experienced i got, the less time i could handle.. I really do believe the heavier you lift and bigger you get, the less time you can spend in the gym. That being said, my workouts still vary in length depending what i'm doing. If i'm doing mostly heavy compound exercises, i'm normally fried in no time at all. I don’t do many sets or workout for more than 30mins. But if i'm doing more isolation exercises, then i'll probably work out for around 45 mins too. I can defiantly do a few more sets before i feel i'm done. I find mixing it up the best for me and avoids over doing it.
Anyway! I think you probably know whats best for your body, i'd just go by feel. As long as your muscles feel well fatigued, but you still feel good then great! If you're dragging yourself out of the gym half dead, then maybe you're over done it. Basically if you keep growing, keep doing what you're doing, if you're not, then i'd try mixing things up!
