I wouldn't experiment with food before running. Eat what you'd usually eat, at the same timing before the run you'd usually eat. This may be inconvenient in terms of waking up and all that.
Check your breathing re side stitches. If you're breathing on the right foot strike, for example, change it to left. Or change to every third strike (in-2-3, out-2-3, etc.)
ISTM that both of these issues usually get worked out in training.