Nothing too major... But today I went to go to class and my tire was dead flat. I hadn't ridden it for a week, but eh. Anyways I pumped it back completely full, and after 12+ hours it was still completely full.

Is there any reason why it randomly went flat? Should I replace the tube to be on the safe side? I don't want to get stranded if it's going to crap out on me. I don't like changing the tube, but if it's best to do so I will lol