Hi all. I recently got my Omer Ice fins, and when I tried it on without socks, it felt loose. So today I went out and got me a pair of Mares neoprene socks, which are 2 or 3mm thick. I tried my fins on again, this time with the socks. The front of the foot pocket still had a bit of space for my foot to move sideways, and if I forced my foot forward, I could force my index finger in the heel. Is that ok? Or is it too loose?