Complexity of simplicity

When I think of defining myself normal, the first thought that comes to my mind is that this is the way everyone is and I must put myself in a mold in order to fit in the society. The world that contains my friends, family and people I come in contact with on a day to day basis. A completely "normal" world. Maybe that is why I try to suppress my thoughts the moment one of my friends talks about a movie that I feel is way too cheesy, unreal and sees the world through rose-colored lenses.
Maybe that is why I listen to my parents going on and on about how I must not care about things that might make me think too much. Because thinking too much can finally make you a skeptic where you don't trust anyone else to make a simple decision on your behalf.
I have always struggled with the idea of thinking simple. I remember my 6th-grade math exam, where I solved the tough questions but was fighting with the simple questions and finally failed to see the questions' simplicity. I used to see this billboard on the beach saying "think simple" and at that moment I would promise myself that I am not going to fight this much. So, I tried distracting myself whenever I felt like I started thinking too much.
Ultimately, I failed. I still think too much. Too much about the conversation I just had with some random person. Too much about an ex, who himself seems to be an overthinker. Too much about tomorrow. Too much about now. Too much about the past.
This has made me a little "negative" according to the people around me. But sometimes I overthink about this too and come to question. Is this actually making me a skeptic or a realist? Am I maturing too much for my age? Am I actually not "enjoying" my life by not going out on those aimless hangouts?
I am still not sure if I am the only one who has these thoughts. Sometimes I look at all the people of around my age, chilling, laughing and just hanging out and I am thrown into a mess that I call my mind. I look at all of them and wish and pray that I could be just like them. Have the time of my life without thinking too much about a mindless comment.
I fail to see the simplicity in the situation.
Now after moving to this new place in a new year, I have come to a conclusion or at least wobbly path to it.
Maybe life is not that tough or difficult to deal with. Maybe living in the present and not giving a shit about the things that happened or might happen can make me happier. Maybe laughing (and sometimes cussing) through all the shitty situations can actually make all of it better.