Hard lumps normal during breastfeeding?

So I'm kind of freaking out. There's this perfectly round, little hard ball in one of my breasts. It's on the top, and it doesn't move when I wiggle the boobies lol. But it definitely raises the skin a bit. I am exclusively breast feeding, and just got done getting rid of engorgement as my baby boy has begun to sleep through the night! So I'm still adjusting to the new schedule.

So could this lump be due to this schedule change, or could it be something more? I just moved halfway across the country, so I have no health insurance, nor doctor to call up. That's why I'm turning to you ladies, for advice or past experience

Thank you ladies!