MGUS Diagnosis: Serum Protein Electrophoresis Test

In April 2008, I was diagnosed with a small monoclonal protein of 0.2 g/dl.  Diagnosis was made by a rheumatologist checking for possible Sjogren's Syndrome.  Diagnosis was made using serum protein electrophoresis (blood & urine).  Immunoelectrophoresis identified the monoclonal protein as IgM kappa. There were no free light chains seen.

A follow-up test in Oct. 2008 also showed 0.2 g/dl, but my follow-up in Dec. 2009 showed an increase to 0.3 g/dl.

Other than the serum protein electrophoresis test, no additional tests related to MGUS have been run.  The rheumatologist feels that, given the low level, no additional tests are needed.  Is that correct?

I am a 60 yr. old female in otherwise good health.  I was diagnosed with IBS 4 years ago and osteopenia about 5 years ago.   I am concerned at the increase in the MGUS level, and am wondering if a visit to a specialist (a hematologist?) would be a good idea?
                                                                                             Thank you.