Greg Tansey's first-half spot-kick put the hosts in front but after the break Kyel Reid curled in a sumptuous free-kick to level up proceedings.
Stevenage had their chances to steal it late on, with Oumare Tounkara going closest, but they had to settle for a point in the end.
"We changed things around at half-time and it was a lot better and a lot more like how we know we can play in the second half," he said.
"We know this is a tough place to come and that they would make things difficult for us and they didn't disappoint. The response we got in the second half was terrific.
"They made it difficult all over the pitch and you have to stand up to it first and foremost. I've seen games here where they have rolled teams over and credit to the boys, they really stood up to it. We got a terrific goal to equalise and I thought we could have gone on and won it.
"I said to the lads at half-time that even though we were behind in the first half we still had some good moments and chances to score. If we could up the ante all over the pitch we could get back into it and we did that really well."