Hello my friend
When I was 13 years old (17 years ago), I started to contemplate about life. "What is it?" and etc. I questioned the life, the existence and Allah. What if we were conned? What if Muhammed was a liar? If Islam is true, how will be eternal life in hell or heaven? Who am I? I cant run anywhere away myself. I came to the conclusion that there was no Allah. No extraordinary power. I felt shock and fear. I wish I was not born, because I was completely lost and could not handle the reality. As if the whole existence was squeezing me. On that day my happiness vanished. The following days I contemplated further. I did not have internet or books about it, so I was just thinking and thinking. I remember, once I was so scared, I hugged my mom and said "mom, I am scared, there is no Allah" and she hugged me and cuddled and said "there is". But I did not feel good. I did not feel security in the arms of my mom, which I always felt there. This state continued for a while and I forced myself to believe Allah. I tried not to think about it and believe without questions.
Allah was my safety. I was enjoying my life and finding everything meaningful until that day. Since that day I lost interest in everything and became in autopilot mode. However, I was a good pupil and studying all subjects very well at school. But in the background there was always discomfort. When I was 17-18 there was a kind of break in my existential thoughts, because I focused on my studying as I was preparing for entrance exam to university. As I passed the exam, the existential thoughts came back. I decided read Quran with the hope that I will find the ultimate Truth there and find relief. But as I started to read Quran, I got frustrated a lot, as obviously it was bullshit. Then I surrendered to my thoughts and became an atheist. Afterwards I stopped thinking about these issues so often.
But I got other thoughts subsequently. As I still was looking for an absolute thing to rely on, a thought came to my mind that I must be brave and should feel no fear. I even tried to stab myself to prove to MYSELF that I am brave. Of course I did not have guts to stab myself, so I again got that discomfort. I was doing different things to prove my courage to myself. When I was not doing these things I was feeling uneasiness in my soul (or psychology). After some time I figured out that this is something abnormal. (It lasted 3 years). I resisted the urges and buried those thoughts. And then I thought that I never had a girlfriend and I never kissed a girl. Before it almost never bothered me. But now I felt discomfort in my soul, and I started to spend a great time and effort to get a girl. When I got a girl (to be honest I got her after two years) I said to myself now I must get second and etc. All was to prove to myself that I was not a loser, my life was not a failure and etc.
I felt I was not normal and searched internet and saw that my symptoms are OCD.
4 years ago I visited a psychologist after a mental crisis and told her everything what I had went through. She said that I have OCD. That I am looking for control, certainty and absoluteness. I was prescribed antidepressants. She helped me a lot to understand my mental state. But overall I am still not happy and not contended. I still have mental crises and sometimes get existential thoughts as well. Especially when I overcome obsessive thoughts about girls. My mind always finds something to contemplate about.
By the way your case is not your fault and you dont intentionally think about those things. It is also type of OCD. It is your brain.
http://www.wsps.info/index.php?option=com_content&view=article&id=140:to-be-or-not-to-be-that-is-the-obsession-existential-and-philosophical-obsessions&catid=0