1500 mg of magnesium per day is quite a bit, unless it's something like magnesium malate where the 1500 mg is not elemental.

The calcium magnesium ratio is important so if one is too high, you're not getting the benefit of it, because the other is not in balance. Calcium and mag are both synergistic and antagonistic.

Unless you are eating a high calcium diet, 1500 mg magnesium may be too much, so I would take a look at that and maybe drop down the magnesium some.

The other consideration with magnesium is always if it's a well absorbed kind. Mag oxide is the kind found ubiquitously, but it's not well absorbed; only 5% according to one study. Magnesium glycinate and mg taurate we both well absorbed and are especially good for stress as well. Magnesium malate is good too, as is mag citrate, which is often recommended for its laxative tendency if that's relevant.

I've also started taking magnesium threonate which is said to cross the blood brain barrier, so may be especially good for depression and stress. It's also anti-inflammatory to the brain, per one of the doctor's I recently listened to from the Arthritis Summit.