John Akinde put the hosts in front in the 16th minute and Danny Green scored twice before the break, his second from the penalty spot after John Spicer's foul on Akinde.
County defender Graeme Lee was shown a straight red card for his professional foul on Jon Nurse and although the visitors notched a consolation when substitute Njogu Demba-Nyren headed home Spicer's corner, they crashed to a seventh straight defeat.
Still said: "The first half was very good then I think the nerves kicked in. I said before the game we're going to play some games now where we encounter nerves.
"I don't think we handled them too well, but it's important to win. In the first half we got the three goals and we had a couple cleared off the line.
"I think even in the second half one could have gone in for us, but the most important thing we can do at the moment is win, that's key. It's not about playing well. We've been playing very well of late, but it's about winning."
Source: PA
Source: PA