Seriously need help!! Bump on nipple!

I have a bump on my nipple that's got larger over the last few days..

I am going to the doctors tomorrow as it's not open today just wondered if anyone has experienced the same kind of thing?

I'm not breastfeeding but I am 29 weeks pregnant.

At first I thought it was a spot but as it is only getting bigger it's fairly sore and looks like it may have some pus in there?

Me and my partner joke I'm growing a third nipple but in all seriousness I am quite worried

Can anyone shed some light?