My cello bridge popped off?

You definitely responded appropriately. But, as has been suggested, you should definitely have it taken to be looked at. The bridge might be warped, and it also must be placed absolutely precisely. You might want to see what's going on in your house with the humidity. Moisture in the air is absorbed by wood, and that can cause your instrument to warp. In general, you want to keep an instrument in an area with 40-60% humidity. If your house is consistently rather humid, you might want to consider investing in a dehumidifier. They're not, cheap, but compared with the damage that humidity can do to an instrument, they can be well worth the cost.