Exercise affects BG levels in different ways depending on length of time, type of exercise (cardio vs resistance) and how fit you are at that type of exercise.
Typically, weights would increase BG and cardio would reduce BG so if you did your weights after cardio, a higher BG is not unexpected.
You may find short cardio or interval training will also increase your BG.
Keep an eye on your BG in the next 24 hours as you may find it will start to fall: in order to raise your BG, your liver has done a sugar dump; this may mean it has less sugar left to "drip" throughout the rest of the day.