I wouldn't worry unless he is listed in the injury reports.
ant555 has said this in another thread but work loads are managed. There is threshold level of work for a player to have completed to be in the range of optimum fitness (at least in terms of what the training program is trying to achieve). It would likely equate to about 80% of sessions (which is not to say that's the only way the level can be achieved). If Draper has been flying to this point, and worked hard over NYE, he could already be close enough to the required level to be 100% for a practice match in 2 weeks. At this stage it could just be about maintaining the gains of the rest of the pre-season.
The reason you pull him from a session is that if he is sore or even hinting at being sore there isn't much benefit, in a physiological sense, to work him into the red zone where an injury is more likely to occur.
Ideally he can just do every session without incident, because that helps with touch, etc, but it's rarely the case anyone can get through that workload at the best of times and particularly while still developing physically. Remember, he's learning how to put a >110kg rig through a midfielders workload.
You told me last year you knew somebody at the club that gives you information, so I assumed that if you made a claim it had some weight behind it, so asked the question here to see if somebody had more information. No offence intended.