Brief Answer:
Can be fecoliths in colon Needs clinical evaluation and diagnosis.

Detailed Answer:
Hi.
Thanks for your query.
To recapitulate: Female/44 - get constipated whenever away from home - noticed lump just above belly button since last Wednesday - have had several hard and darker bowel movements since you have noticed the lump - no pain with the lump - but do feel something off in this area - was going to start a laxative in case the large intestine is impacted - wants to know what this may be and whether to see a Doctor...

With the history your have provided, there may be fecoliths that are loaded in the large bowel and the ones in the transverse colon can be palpable just above the belly button.
Other possibilities are:
Supra-umbilical hernia.
Lymph node mass
Swelling relate to pancreas, liver or stomach or transverse colon.

I would advise you the following:
If there are no other symptoms like pain, nausea, vomiting or bloating you may please try a laxative and see if the lump vanishes after passage of fecoliths (hard stool lumps).
If the swelling still persists after passing these lumps, you certainly need to see a Doctor for clinical evaluation, examination , investigation and proper diagnosis and treatment.

Please give some additional information:
- Is the lump XXXXXXX meaning changes its position on changing your position in lying down position?
- Does it enlarge on coughing or any sort of straining, say like passing stool or increasing the intra-abdominal pressure?
- Does it reduce and vanish completely once you are lying down?
- Any other information that you would like to share?

I hope this answer helps you, please feel free to ask for further relevant queries if you feel that there is a gap of communication.

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