Lump on my abdomen

Hey guys... I noticed something weird on my stomach yesterday—just a bit below the belly button on the left side. It feels like this hard, painful lump under the skin, but only when I touch it, and there’s some slight redness around the area. Honestly, it feels a lot like a subcutaneous pimple. I doubt it's just fat because I read that fat is soft and doesn't hurt. To be real, I have no clue how long it's been there since I wasn't paying attention, but I do remember seeing what looked like a whitehead in that exact spot about a week ago. I tried squeezing it as much as I could, but the area is pretty large and soft, so it was impossible to actually get a good grip on it to pop it.
Has anyone dealt with anything similar?

A constant, heavy knot right between my shoulder blades...
It isn’t exactly painful, nor does it truly bother me in my daily life, though I can't help but notice it...
I’ve actually undergone a few physical exams for work over the years, you see...
And I honestly don't have any underlying medical issues at all...
It seems quite obvious to me that it’s just some sort of gland issue...