Creo 4.0 Parametric student sketch issue

My software is all up to date and registered here is my problem. When i start a new part file and choose to sketch on any face (front,top, right) i can only draw one line demension and it locks me out. I cant draw another line or circle or anything. I can though draw multiple line to form a shape but that is before i demension the lines. My instructor has never seen this before so Im clueless as well. What are my options?