Is it possible to ejaculate too much and ruin your chances for a longer sex life in later years on going?
I recall hearing that statement, which is sort of vulgar, however i will note it here only for medical purposes: "Young, dumb and full of cum."
So, is it dumb to be young and getting off all the time?(ruining later chances)
Not really. Even doing it once or twice a day is not really considered dangerous. Never force yourself though, you have to want to.
I can't remember where I read that but to some extend it makes sense that since we produce a few million spermatozoids per hour, it's good to release once in a while (a couple of times a week is frankly enough).
The real danger is related to temperature and position: not too tight, not overheated (having your laptop on your legs is not good for example), and of course no injury (be careful when doing sports).