Not likely. While some young men may have lower urinary tract voiding symtpoms, they are not likely due to an enlarged prostate as the prostate has not started to enlarge at such a young age. Some young men have a bladder neck problem that looks like BPH and may repsond to some of the same treatments. Your urologist would be able to to the evaluation and recommend appropriate treatment.
Highly unlikely. Consider other issues like stress or infection first.