Yes, firing inside a room will cause damage to your hearing. To what extent will be different for everyone, even firing outside without muffs can and will cause damage.
I would advice the use of a suppressor, 380 ACP is more than capable at close range to end the fight.. I know many will disagree, however, I have looked at self defence shootings and there are plenty one shot stops with the calibre.
You can even go further and use suppressor gel to reduce the DB.
For street carry, I would use something bigger.
Best advice, improve your home security to reduce the likelihood of someone breaking in and get a dog.
I know of someone who used a snubbie 2inch 38 Spl (non plus p ammo) and lost his hearing completely in one ear. The attack took place in a subway..
Koolminx, I disagree with this
“But in my experience and training with weapons, there are no pistols or shotguns that will blind or partially blind you when firing them”
Your eyes have cones and rods. Cones are for day vision, Rods are for night vision. The flash can blind you temporarily, from 1 to 2 seconds or more, for your eye to adjust.
What you need to do, is to shoot your carry ammo at night. There are 4 types of flashes in general, RED is ideal, WHITE, ORANGE and YELLOW. Choosing the ammo is the most important part.
Then practice Rod’s regent shooting, to minimise the affect on your rods.