I am a male and I am 16 years old.

I have a girlfriend that I have been with for about 5 months now and we are VERY comfortable.

We engage in alot of sexual activity and recently we have started oral sex.

I have had a hard time getting an erection in various situations.
-while Masturbating rarely
-During a handjob
-During a BJ
-other Foreplay

But i can still reach climax without an erection so these problems dont really matter of course besides that it affects my pride

I DO get hard in the morning and most of the time I masturbate so I know it is not a physical problem, Plus I am way to young to have a physical problem!?!?!!

Back to the point we have recently tried to engage in sex.

When it comes to sex I am not erect, We have tried 3 times

-The first time I was totally limp and I could not even penetrate
But we talked about it and figured things out and everything was okay so we didnt try for a while.

- The second time we were in the shower and i was semi erect and could penetrate but it was not rigid enough to have sex, it just kind went in and would slip out if i tried to thrust

-The third time I was semi erect and could penetrate but it still wasnt going too smoothly?
It did not feel good and I think its cause I was not fully erect and it was more slipping in and out than sliding. She seemed to like it but as it went on i think my mind got to be and I lost it totally again.

I think I have a psychologial problem, And i am too young to go to a doctor? or atleast too embarrassed and I dont even want to go to my parents because they will get mad I am having sex. I am hoping the problem will just go away on its own?

I am attracted to my girlfriend and I get horny and everything it just doesnt translate into an erection? so What should I do to help this problem? Masturbate without porn and maybe to the thought of what me and my girlfriend have done? So my mind gets used to it and i will get erect?

I also have a problem where i used to masturbate face down Called TMS OR Traumatic Masturbatory Syndrome(http://healthystrokes.com/index.h tml)

I have heard this can cause erectile disfunction because when you masturbate face down you can get off without having an erection? and Im worried maybe i have trained myself to lose an erection to ejactulate? i Have since learned to masturbate the correct way sitting down but I still sort of thrust into my hand as I do it. And when i do stuff with my girlfriend i kinda thrust a little just to make the sensations come around?

Please Help!!!! I am wondering if this is the case there is any way to train my erections to respond normally!? and if its a psycological problem like preformance anxiety or something how can I overcome it!!!