Probleme Regarding Erection of Penis.

Dear Sir,
I am a 26 years old student. I am having some problems with erection of my Penis. My Penis doesn't even erecct when I wake up in the morning and go to washroom. It makes me mentally disturbed.
I simply just want to know that how can I get a clear idea about what my problems are exactly and how can I get a good treatment for these problems. I also want to know that whether I can get a clear solution of this problem.
With Regards,
Zarif Mushrafi