The final outcome meant McDermott's men are still without a top-flight win this term after six games but post-match, the manager was not complaining too much about a potential victory squandered.
"I know what happened in that second half," McDermott said. "Swansea played really well and that is a point gained for us."
The Royals went ahead in the 31st minute when Swans goalkeeper Michel Vorm allowed a Pavel Pogrebnyak shot to squirm beneath him and they doubled their advantage a minute before the break thanks to Noel Hunt's volley.
The hosts had been the better side in the opening half, though, and continued to press after the interval, with Michu's header reducing the deficit in the 71st minute before Wayne Routledge slammed home an equaliser seven minutes later.
Swansea were also thwarted by a string of excellent saves from Reading stopper Alex McCarthy and had claims that Nicky Shorey had handled in the box waved away by referee Mike Dean.
"I couldn't tell you how many, but I do know he (McCarthy) has made some fantastic saves," McDermott added. "So at 2-0, we have got to 70 minutes, but we are just sort of waiting for something to happen on their behalf. We need to affect the game better than we did in the second half. But having said that, that is a good point gained here."
And while McDermott insisted he had not seen the incident involving Shorey, who blocked a shot by Pablo Hernandez, Swansea manager Michael Laudrup was more certain on the matter, claiming the Welsh outfit had been denied a legitimate spot-kick.
"Who knows what would have happened if we got the penalty we should have?" Laudrup said. "It should have been a penalty - obviously, it is football so you can't use your hands if you are not the goalkeeper. But the referee didn't give it and that is what can happen.
"It is a little difficult to say if it was a point gained or two lost - you can say both or neither."