Help me! BATHTUB WATER LEAKS after bath

Hi, I hope someone can help me with this problem.Everytime I take a bath and drain the water it ends up all over the floor.I assume the water is draining from the caulked areas but I think it is also coming from the wall directly behind the tub.The water also leaks, if I fill the tub up with alot of water from the kitchen cabinet floor which is directly on the other side of the bathroom and at the back of the kitchen cabinet is a little compartment with what I think might be a drain or a pipe the bathtub is connected to.The funny thing is when I take a shower, no matter how much water is used, it doesn't leak onto the floor.Please if anyone has any advice for this single mother, I would appreciate it.

1) When you fill the tub, are you filling it enough so that water drains into the overflow just under the spigot/spout?

If so, it is possible the overflow is not sealed tightly to the back of the tub wall.

2) If you do not put in enough water to reach the overflow, does the tub hold water okay and only leak when you open the drain?

If so, something might be loose behind/between your tub and kitchen sink and the pressure of a draining tub rather than a mere shower is enough to cause a leak.

The water never gets as high as the drain opener/closer and holds water fine without leaking until I open the drain to let the water out, then it leaks everywhere.I mean the whole contents of water that is in the tub drains to the floor.Could it be the shower pan or something else simple or do you think it is a major plumbing job?

Since it does not leak when you run the shower, something it probably just loose somewhere. Sometimes that kind of problem can pop up after bumping into the plumbing under a kitchen sink ...

How much of the plumbing can you see there? If you can take a look and can reach through to the plumbing under the tub, gently feel around for anything loose.

My guess is that you have a simple problem you might even be able to resolve yourself after taking a look and asking a friendly "hardware helper" to show you how a tub drain is assembled.