Am I experiencing penile discharge?

About a week ago I was sitting in class and I noticed my boxers felt a little damp. Slightly embarrassed I left class to go to the restroom to see what it was. I didn't have to urinate and I knew it wasn't semen so it drove me crazy, but since I didn't actually see anything I ignored it. I am still experiencing this phenomena now. My boxers will start feeling damp for no reason but no wet spots appear on my boxers or pants. It defiantly feels as if something is coming out in very small amounts, though I have never actually seen this. Also, just last night I started to notice some unusual odor kind of like vomit. However, I'm not sure if that smell was connected or not as I was in someones car at the time. I have not experienced any other unusual symptoms. It's more annoying than anything and makes me feel somewhat awkward in public even though nobody else has noticed. Should I schedule a doctors appointment for this?