Assuming your blood pressure is in the normal range, nose bleeds can be caused by dryness in the air, allergies or even a sinus infection. Make sure you're drinking enough water. If your home environment is too dry, you may want to get a humidfier.
It doesn't hurt to get it checked out.
My husband gets them in the winter because of the forced hot air heat in our home. The rest of the year, he's fine.
Good luck!