well considering you said you were in college. i would say being a college student, not sleeping enough (which is common in college), probably working a shitty job or two, having a shitty college diet of pizza and beer (you don't have money to buy decent food or time to cook it) plus lifting weights at the gym would definately effect a lot of things including libido.
i remember when i was in college fulltime.. i also had a part time and full time job. i would leave my full time job to go to school and i would get there early and eat fast food cause I did not have time.. and i would get home around 10pm, wake up 6 the next day. usually not even eat breakfast.. only time i would have to hit the gym if i was lucky was the weekend after school which i had a class sat morning. OR after work if i didn't have my other job or school that night.
so my recommendation is just chill and get through college and then once you establish yourself then you worry about juicing and lifting. college takes up a lot of time, having to do papers, study for exams, chasing pussy all that shit.. I don't know how you young guys even have the money to afford to juice making $8 an hour .. guess kids these days are spoiled or something