Adhesions, hernia, or something else?

I have lower left quadrant discomfort which I suspect to be either adhesions from a surgical procedure four years ago,  or a hernia that may also be related to that procedure.  But I've never had it thoroughly checked out and it has recently gotten worse, so I'm a little concerned it could be something else.

My profile goes like this: I'm a male, 56 years old, good health, athletic (still) ; I have absolutely great, regular bowels, no family history of cancer (well, my mom just got diagnosed at age 80 with stage 1 lung cancer but she smoked for 40 years).   I may have a propensity toward hernias -- had an inguinal hernia repaired as a child, and have had an umbilical hernia that has never bothered me much and never been repaired.  Six months ago I had a physical  with a  full set of standard bloodwork done six months ago, no problems noted except for high cholesterol (but with a very good HDL/LDL ratio).  All blood chemistry was right in the middle of normal values.

The discomfort in my lower left quadrant first manifested in 2004 after I had liposuction to remove subcutaneous "belly fat" and "love handles".  At the time the doc told me he had been "pretty aggressive" because of my overall good health and muscle tone.   During recovery I had discomfort/stiffness in each of the main areas where work was done.   Eventually the discomfort went away everywhere but the lower left quadrant, which remained a bit stiff much longer than the other areas.  However, as I dieted and lost weight over the next year,  the discomfort pretty much went away, although I could feel it if I really thought about it or moved in certain ways.

That was 2004-2005.   In 2006 I gained weight (10 lbs) and the stiffness returned. In 2007 I lost weight and it went away.  In 2008 I gained weight again and it came back -- and this time it's been more pronounced than it was previously,  although it still comes and goes.  It definitely is much, much more noticeable when I gain weight.  It is relieved to some degree by wearing an exercise belt; it bothers me mainly when sitting down and is more noticeable just after I eat, particularly after a heavy meal.  If I have an attack of  gas (which I have rarely) I can feel an extra twinge or extra awareness. Ditto if I'm constipated.   I've experimented with fasting for a few days at a time (even when my weight is up a bit) and it doesn't go away - but it's diminished.  (And I generally have great, regular bowels - no hint if IBS or anything like that.)   There is no sharp pain or radiating pain or anything like that -- just a pulling sensation, or tightness.

There is no lump per se, when my abs are in a normal state of reasonably well toned musculature.  But if I consciously relax my abs -- there seems to be a kind of swelling that is visible.    I sometimes feel a twinge in the area when I bear down during a bowel movement; and lastly when I rap on the area doing my imitation of an internist, the sound I get is "tympanic" -- not "dull".

So ... does my self-analysis make sense?  How worried should I be that it's something else?  Is there any way to rule out bad stuff without going through a colonoscopy?