Need some tips

I'm currently on day 2 or 3 of pumping (my days are a lil blurred right now) and my nipples are on fire or so it feels after pumping. I already had DDD boobs before any milk supply came in but its working it way in now. I pump every 2-3 hrs trying to keep up with my NICU baby's feeding and so I'm a lil sore. Any tips on something that would help my poor nipps but not effect my supply? Thanks in advance and sorry if this was hard to understand I'm half asleep still lol