I had something similar when my marathon training ramped up and went to the physio. The diagnosis was weak calves! Basically my calves weren't strong enough to handle the load. Some dry needling and a course of calf raises sorted me out. Not sure if you're the same but I'd always er on the side of caution and see a physio. Also - the carbon shoes generally put you more up on your toes and put more load on your calves.
I had something similar when my marathon training ramped up and went to the physio. The diagnosis was weak calves! Basically my calves weren't strong enough to handle the load. Some dry needling and a course of calf raises sorted me out. Not sure if you're the same but I'd always er on the side of caution and see a physio. Also - the carbon shoes generally put you more up on your toes and put more load on your calves.