Drinking, but not swallowing?

Sable, one of my female BPs just did something that stunned me.

She's never done this before, so I'm very confused..

I cleaned her tank out, changed her water and I put her back in her tank - all normal. She DIVES under the water, takes a few gulps and just sticks her head up.. Okay - whatever. She then takes some more gulps and leaves her head stuck in the water dish. I had to move her hide and her water dish so I picked her up. She was fine - till her head got out of the water. All the water she had drank just started coming out - just pouring out like out of a faucet.

It looked really weird - and I had never seen a snake do this before. She hasn't been acting weird, ate fine, I saw her soaking her head yesterday. The humidity is 65%, but I've also had the lid off for about 30 minutes, so its probably gone down a bit since I opened it up.

I've just never seen a snake do that - I didn't know if its normal, or if something might be wrong.