What does it mean when you eat magic mushrooms and you feel depressed after?

So my best friends and I got together yesterday for the first time since we've been at college yesterday and we ate some magic mushrooms. We smoked a little bit after taking them and initially we all just felt really high, then tripped a little bit while my other sober friend drove us around. I don't think I had a bad trip, but I felt weird the whole time and none of us ever really got into the euphoric state that everyone always talks about while tripping. After about two hours, we went back to his house and all of us began talking about how we all felt sad and depressed for no reason. At this point we weren't tripping anymore, but we all definitely felt weird and very down. It wore off after a while and then I went to bed, but when I woke up today I still felt a slightly weird and inexplicably a little bit sad, and I still do. I was wondering if anyone here has had a similar experience and can tell me what might be going on. Please help, I'm wondering if maybe they were just bad mushrooms.