Why the downvote? I know I didn't answer his original question, but I was worried for the OP. If you think I gave bad advice, explain why.
There are certainly groups you should avoid, but the majority of the people in our local jail are just normal people who got caught with a little marijuana, or racked up too many DUIs. In other words, they're a lot like the OP. IMO, there's no need for alarm when going to jail.
only thing I wouldnt agree with is stand up for yourself no matter what. there are times when walking away just works. sometimes people just want to be the alpha, and the smart thing to do (many times) is to let them do that.