What a perfect site to post this on please help me out here...

ok so a few years ago I could have sex all day everyday. But now it's one and done... It might not seem like a big deal but I'm 19 years old. I should be at my peek. Peak* however you spell it.. it sucks because I get really turned on and when I bust it's like I lose all interest.. I can get hard again shortly after with a ha****b/blowjob. But when I try to have sex it's a floppy and no good. my girlfriend doesn't seem to mind but sometimes I would like to have multiple orgasms with her!! i have no problem getting hard the first time, and no problems with not being able to last long.

so here's a couple things that I think may be affecting me.

i smoked a lot in the past year(marijuana) but I've quit thinking it will help

i have varicocele on my left testicle. maybe that is bringing my testosterone levels down

maybe I my diet should be better... Even tho when I was younger I hadda a shittier diet.

im more active than before I go to the gym often

i don't cum a lot. (The amount of cum) I'm not sure how much one should cum. 

my girlfriend is really good looking so that cant be it. Ughhh I'm going crazy 

also this might just be me being crazy but when my penis is soft it's pretty small 2-3 inch and when it gets hard it's 6-7 inch im not saying I have a big penis but I feel like it needs a lot of blood to fill up. 

someone please help me out here. I'm too young for this. So can ejaculateMultiple times through the week but c'mon I'm trying to go back to back thanks for reading!!!