If you have diarrhea so bad that it sounds like your vomiting, your eyes water and your sniffling then you better get them to the hospital asap as they will get dehydrated to the point of death (diarrhea is the number one symptom that kills more people than the issues its a symptom of) very quickly, and what ever is causing probably isn't a joke either.
In short no they sound very different, and your roommate is in help either way eating disorder or very bad diarrhea both won't end well unless treated.
I guess what I am saying if he/she is your roommate not you best buddy don't be afraid to approach them about it, as long as they keep paying their bills hurt feelings don't matter, but a burned out esophagus does.
On a side note if you can hear the roommate make a audible sounds like errraaaearrrrraa just before the noise then puking is more than likely whats going on. (I'm guessing that's what the fan/shower are meant to drown out)
Edit: In short yes I believe your roommate is puking as vomiting and shitting in no way shape or form sound familiar and he/she is obviously covering it up with the shower/fan...come on who turns the shower on every time they enter the bathroom.
