I Have Like A Knot Forming At The Bottom Of

I have like a knot forming at the bottom of my stomach close to where I had a C-section 19 years ago. I'm a bit overweight and I carry it in my lower abdomen, so when I lift my stomach it hurts. It hurts even when I'm not touching it. Just a constant pain that's been going on for over a week. I am a diabetic
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