Shane Long and Marlon King both saw their efforts hit the post in the first half.
Long and Jem Karacan then went close after the break but could not find a winner as Reading recorded their fifth successive draw.
McDermott said: "We dominated the game and should have won.
"In the 87th minute Shane Long had a chance to win it with a header. In the first half we dominated but the goals aren't going in at the minute and in the Championship the first goal is very important.
"I have never been involved in a team that's had five successive draws, but on the positive side that means five games unbeaten."
Source: PA
Source: PA