I'm starting to get a small bump inside my mouth.... i'm assuming its a syst. does anyone know what it could be! i'm going to the dentist today?

Many Possibilities: May be the beginning of a dental abscess, cyst, salivary gland , etc. The good news is that you are going to a dentist who should be able to tell you what is going on.

Need to see to know: A small bump inside your mouth could be one of many different possibities. Each possibility has a different treatment, so it is very important to determine what exactly the bump is and what is causing it. The bump could a cyst (as you suggest), a gum or tooth abscess, a fibroma, etc. Glad to hear you are going to the dentist today for an evaluation and treatment as needed.