One of the side effects of Adderall is a pronounced increase in muscular tension or tonus, with a corresponding lack of that looseness which stretching and warming up provide. Range of motion decreases and antagonistic muscles work against the prime movers. That was likely a primary factor in your hurting your hamstring.
Your concise report also suggests other Adderall effects which may well have contributed to your injury. You were 'training well and feeling great,' which sounds fine at first. But a main effect of Adderall is to produce a greater feeling of well-being than a given objective reality would normally indicate. This can reduce and distort the feedback upon which we depend in decision-making. Some Adderall users experience impaired ability to discern harm that their behaviors cause, and to learn from experience, and to avoid the harm. For runners trying to fine-tune their training, the potential problems are clear.
Adderall, being a stimulant, can increase the strength of muscular contraction, which also increases the chance of injury.
Adderall impairs balance and coordination, thus raising the chance for injury.
Then there are Adderall's therapeutic effects: increased focus and concentration may have contributed to a workout where you were not just training well, but too well. Workouts too intense, or too long, or too often.
Adderall greatly impairs our capacities to stop whatever we're doing, and to switch tasks. These effects are helpful for studying. Adderall causes perseverent behavior, and in running training, where we are always trying to find a happy medium short of overtraining, the potential for injury is there. It is quite conceivable that Adderall might impel us to hammer a workout when we should back off or abort it.
Inadequate nutrition and dehydration could be factors, as could lack of sleep. When sleep-deprivation impairs cognitive ability, no sign lights up to proclaim the fact, and the user may be unaware that he or she is significantly less able to figure out what to do. Adderall stimulation may mask accumulated fatigue, increasing the chance of injury just as it increases during the fourth quarters of long games. .
You did not mention your Adderall dosage (or how long you've been on it), but if it is enough that you notice appetite suppression, it may well be enough to cause other effects you may not be aware of.
Not implicated in your injury, but something bear in mind, is that Adderall treats hyperactive persons, and very effectively at that, It can turn a hyperactive person into a couch potato. For this reason, and those above, and others not mentioned here, it can have a dramatic adverse impact on one's running.
Best of luck to you.
I am a runner, but not a doctor, and disclaim responsibility here -- yet there are some reasons not to dismiss my points as internet chaff. I have been on Adderall for 5 years, prescribed by a doctor of internal medicine and psychiatry. I took all the courses in the school of medicine that the university would allow me to, as I was not pre-med. I have some medical background and have researched amphetamines extensively.