Rash after pumping/feeding?

I breastfeed and also pump and bottle feed *Please don't tell me to not pump, it's necessary, long story, feel free to message me if you're just that interested in knowing why*

So after I pump/feed, I get really itchy on my breasts, not just my nipples but everywhere. It gets really red even when I don't scratch and the "rash" is hot, but then goes away on it's on 5-10 minutes after pumping/breastfeeding... It doesn't bother me any other time except when I express milk some way or the other... Does that still sound like a yeast infection? I haven't noticed anything in my sons mouth or any symptoms with me but he does have a doctors appt tomorrow morning and I am asking her to look...

Does it sound like a breast infection or just normal irritation?
Sorry I'm new to this!!