Loud noise when going to sleep after going to the bathroom?

[Crocodilian123]

I get up to go to the bathroom every night. When I'm falling back asleep I hear a really loud noise, I can't even describe the sound, and it wakes me up. Is this the transitional stage of lucid dreaming?

[Bluefirephoenix]

It's probably an opening of your psychic senses and it's being interpreted by your body as a loud sound.

I am very glad I don't get that much anymore. It was very obnoxious when my clairaudient ability started to work.

[Projector4life]

Hypnagogia state

[Szaxx]

The noise is perfectly normal. You're in the hypnagogic state and your senses are being switched away from your physical body. The last is typically hearing. The creaks and taps as the house settles can be heard normally and are ignored as you fall asleep. You know they exist and have automatically ignored them.
When in the hypnagogic state, these noises are still present but they interfere with your sleep onset. This creates another sound and a simple click can be extended and it sounds like a metallic zing. The sound you get on occasion when a digital sound track is damaged and the equipment can't decode it. You get a metallic buzzing sound. It also appears in fringe signal areas on your mobile/cell phone. It's harmless but annoying as it wakes you so your ears function normally. By then the click has gone and you think the daleks have invaded lol.
I've experimented with this state thousands of times and still do. You can create any sound too. It's amazing that the sounds/voices you hear when fear grips you while in SP are self generated. No-one seems to be aware that they are only scareing themselves. The fear is usually intense.
Next time you get to this stage, imagine you can hear your favourite song. Listen for it and it will appear. Don't get scared, its normal to be scared the first few times. You'll hear your tune and with practice you can change the lyrics too. This is fun as you can let your imagination run wild. The sound is like the band is next to you. The clarity is perfect.
Have fun experimenting.

[Bluefirephoenix]

Yea the sound creating thing can be really creepy.  You can mix the senses too which is kinda trippy. So listen to the color pink