Colon discomfort - does this mean anything serious?

I've been in recovery from a chronic brain injury for about 7.5 years now and, while I'm often difficult to tell there's anything now wrong (in most places, not all as tension/stress worsens symptoms), there is one problem I've had from the start which I'm wondering if anyone knows if this is something worth considering as being serious (ie pre cancer) or just wear and tear.

My bowel muscles were damaged by this brain injury virus (it basically ruined my central nervous system for about 5 years) and, initially (ie the first 2-3 years) I was averaging 5-10 bowel movements/day before it began to be less frequent.

It's still somewhat frequent (4x most days) but now there's a new(ish) problem which has arisen : pain during a bowel movement (as opposed to sitting or standing, when there is none, so this is obviously internal).

It basically feels like a large pimple is being squeezed inside me as I push (apologies for the visual) - that kind of sharp pressurized pain (but not 'OH MY GOD' bad, more just a real pain in the a$$).

I read the symptoms of colon cancer and those don't sound consistent with my issue but I'm concerned nonetheless.

If you know anything about colon issues/pain/illness and this sounds like something to worry about, can you please tell me what medical condition it sounds like to you? (I'll ignore stupid comments)

Advance thanks.