If you felt like you could have gone longer, then I'm sure you could have gone longer. Two things worth noting, however:
First, it's good to have a minimum amount of time in mind for a meditation session, and stick to it. You can always stay seated after your timer goes off. Without a firm minimum, it's very easy to stop as soon as you get fidgety. Speaking from my own experience, sitting through fidgetiness has been the immediate precursor to some of my most meaningful progress in meditation.
Second, consistency is more important than intensity. My (personal, inexpert) recommendation is to choose a time that you can manage every day, and stick with it. Don't over-commit, or you may get burned out. For me, 20 minutes is about right. YMMV.
First, it's good to have a minimum amount of time in mind for a meditation session, and stick to it. You can always stay seated after your timer goes off. Without a firm minimum, it's very easy to stop as soon as you get fidgety. Speaking from my own experience, sitting through fidgetiness has been the immediate precursor to some of my most meaningful progress in meditation.
Second, consistency is more important than intensity. My (personal, inexpert) recommendation is to choose a time that you can manage every day, and stick with it. Don't over-commit, or you may get burned out. For me, 20 minutes is about right. YMMV.
Stick with it! It's very rewarding.