It sounds as if your doctor is being thorough in his follow up. You stated in your post above, "I’ve never had any problems like this before, and to be honest I am scared. Should I get a second opinion?"
Please know that it is always your right to get a second opinion. The second opinion would best come from a large university medical center (where there are a lot of specialists who consult and work as a team) or research-oriented hospital such as a Mayo Clinic facility (there are three, in Minnesota, Florida and Arizona).
Please keep in touch, I look forward to hearing how this problem is being resolved and what you are doing to reduce your anxiety about this diagnosis.