I Have Had Slight Tenderness Next My Navel For The

I have had slight tenderness next my navel for the past 10 days. I can feel a very slight bulge if I press the area. I recently lifted a fairly heavy table, and think that is when it began. I have no other symptoms. It does not feel worse during activities. I only feel the tenderness when the area is pressed on. I am a 48 year old female, 5' 8" and 175 lbs. Will it go away on its own? Should I rest and avoid activity? Is there any diet recommended? I have no family history of hernias. I have had 4 children, the youngest is 13. what else could this be? Do some people not have surgery for slight hernias? would I need to avoid straining for the rest of my life, or could it heal on its own?