S.V.
Hey R.! I love posts on breastfeeding because I was able to nurse my son for a whole year (he just turned one 2 weeks ago so I still miss it!)
I had the same pain that you had SEVERAL times, I even think I had a yeast infection at one point but I nursed him more often and it went away. I went to the doctor a couple times because of the tenderness, and the hardened spot, or a sharp pain in the nipple, I was advised to nurse him more often and make sure he is drinking. It always went away.
When I would pump to help "drain it more" because I thought it was a clogged duct, I seemed to get less milk. So, I quit pumping and just reverted back to nursing more often.
I do know that if you run a fever, or begin to get red spots, and it feels warm over the tender spot, go to a doctor because it could be mastitis. A warm washcloth can help as well.
As far as drying up, when I was weaning, and even still today, I sometimes get a tender spot and I assume its because my body is drying itsself up, so I cannot speak for your situation because I forced the weaning so.. good luck and I hope it works out that you get to keep nursing him, its the BEST!