Hi . So the last few weeks I've had trouble getting my penis even half hard. Usually it'll stand around 7" but lately I can barely get 5"and it's not even hard enough for penetration. I take 25mg of zinc daily and l arginine plus niacin. A few weeks ago I could get hard even with the the thought of being with a girl. I'm not sure what has happened. I train 4 days a week HIIT, sleep a lot, cold showers daily ( never ever take hot ) and drink a lot of green tea. I have been a bit stressed due to this as I slept with a girl 2 weeks ago and could barely get it up and keep it up. I'll admit I've been stressed and lacking confidence lately due to losing my apprenticeship in engineering back in August. However I have a few interviews coming up for other ones. I've begun to think it's nerves but I have no idea how to calm myself. I'd appreciate the help guys. Cheers and have a nice day.