Brief Answer:
It could be normal pulsation

Detailed Answer:
Hi,

Aorta is a major blood vessel which runs in the middle of the abdomen. In some thin individuals these pulsations are felt per abdomen. Many people mistake them as a disease.

Because of previous surgeries, there is possibility of adhesion leading to intermittent pain. However it may not be related to those pulsation. If the adhesions are severe, there will be complaints of vomiting, constipation and distension of abdomen.

Lymphatic problem has no relation to it. It may cause leg swelling.

In brief, your symptoms doesn't concern me. If you are in doubt, get an ultrasound abdomen to confirm the diagnosis.

Hope this helps. If you have any queries, I will clarify further
Wish you good health
Regards

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