If I did not get a job because of something cosmetic or just a bad feeling what do I do?
Unfortunately most companies don't tell you why. They are usually interviewing so many candidates that it's hard to write individual emails to everyone with feedback. It stinks I know, but following up asking why you were rejected won't necessarily help you. I think you should gracefully thank the people you interviewed with, tell them you would love to keep in touch, and try and refrain from further inquisition. You are going to face rejection sometimes, but life works in funny ways and you never know who ends up where and if the opportunity will present itself again. Just move on to the next opportunity, which is probably right around the corner, and maybe it's an even better one! Also, it's super illegal not to get a job for cosmetic reasons.
Reach out to the hiring manager or HR representative to find out more information about why you were rejected. Ask what you could have done better during the interview.