Hi,
I don't know if what I'm experiencing is similar to you, but for the past few days I've been getting pains inbetween feeds just on one side, but I think it's starting on the other breast too. Sometimes also towards the end of the feed it starts getting a bit sore and uncomfortable, like a rough feeling on my nipple.
It's not a constant pain but it comes and goes, like a tingling sort of pain, but sometimes it's like a throb, but it's not overly painful. I noticed that it seemed to happen more when I was cold. When I get out of the bath or shower my nipples have always been particularly sensitive. Sometimes my breast pads feel uncomfortable like they are rubbing on my nipple.
Someone on here asked if my nipples go white at all, which I didn't think they did, but now I'm actually looking they do seem to lose their colour or go white on the tip especially after feeding. Google blanching and Reynaulds when breastfeeding and see if it sounds like what you are experiencing.
I think this is what's wrong with me, I think very early on when breastfeeding was new to me I had the same sort of symptoms but thought nothing of it and it seemed to go away but 10 weeks later it's back!
I hope this helps you a bit, even if you can rule this out. I know what it's like when something's wrong and it's worrying not knowing what it is. I absolutely love breastfeeding and it's such a worry when you think something might jepardise it!
Also, I don't have any faith in my GP so I didn't want to go and see him about it, he's clueless when it comes to breastfeeding, he told me to stop feeding my LO on one side when I had a blocked duct and he's told me that "if I like" I can start giving LO a bottle of formula a day! Anyway, sorry I'm rambling!
I might give our local breastfeeding group a call instead!
Heather x