If you're sexually active there will always be the chance of contracting HPV. You don't even have to have actual intercourse to contract HPV, any genital to genital or genital to mouth contact can transmit it. And like many other sexually transmitted diseases/infections, males frequently don't show symptoms of having it and con pass it on unknowingly. Some strains of HPV cause genital warts. They don't always hurt or are bothersome and they don't always have the same shape and size. Some can look like little projections of skin while others can look like little caulifower shaped bumps. In order to find out exactly what it is, you have to see a Dr. If it is in fact a genital wart and you don't have it treated, it will actually continue to get bigger and you can develop more. Also, the entire time it's there you are potentially spreading it to other people, people who can then give it back to you once your's clears up and it becomes never ending cycle. The Dr. can remove the warts in a relatively painless way.
I know going to the gyno for the first time is embarassing, I've been there, but it's a part of life. The first time is like ripping off a band aid or jumping into a cold pool, at first your nervous/hesitant but seconds later, you're fine. When you go, don't even worry about what the Dr. is thinking as he/she is examining you, they're just doing their job, they're not making any personal judgements about you. Many gyno offices will allow a nurse to be present in the room while you're being examined to help put you at ease. As far as being too embarrassed to tell your mom, I've been there too, it can seem mortifying. But remember, when she was younger she felt the exact same way about going to the gyno for the first time and about telling her mother. It may not be a wart, it could be something else, but if you're truely concerned about your health and well-being you need to go to the Dr.