i am a 22 year old college athlete and i have had sex with numerous women before and i was always able to ejaculate after a few minutes into having sex but keep my penis erect to continue on after for as long as i wanted. i currently have a new girlfriend who i am very attracted to and i have been with for about 2 months now and everything was good until a few weeks ago when i came back from a week long training camp with my team. we had great long lasting sex before i left but when i came back it did not last very long because my penis was not staying erect, and i thought it might have been due to the fact that i had a rigorous week of training and my body was just tired. it has been about 2 weeks and the problems are still continuing. my girlfriend is very understanding claims not to care but i would just like to be back to normal and please her like i know i can. we do not use condoms and i am willing to try anything to get back to my normal self and stay that way. please any advice would be helpful.
Thanks,