sounds like stain on the muscle/tendoms
dont forget your working them harder then they probably have ever worked before at a constant level so theres gunna be some pain as the muscle begins to grow and adapt. this is where muscle memory comes in to play which is why keeping up a ruteen is important.
do some stretches every couple of hours nothing over the top just be gentle, as this all helps with healing and growth.
is its still giving you some trouble try the old hot cold trick as that'll help to.