Wanting to quip, but answering very seriously as this is important. I go to the loo before, so if I need to pee during, it's not normal and already an emergency.

Important:

When you're trying out any kind of bondage, always make sure there's someone around taking care in an emergency.

Read up on how to do bondage with quick release built in. (For example keeping medical scissors around to safely cut ropes)

There's all kinds of stuff which rarely happens, but if it does there's urgency. Medical problems, fires, everything else where you need to quickly vacate the room where you are in.

If you are bound someone needs to regularly check on you and keep in call for help distance.

In fact ropes are one of the really dangerous bdsm toys. Go to workshops where you learn how to use them safely.

(I had a wrist injuriy once due to badly applied ropes. Fortunately it healed after a few months and was just minor. But it was enough to make me scared and directly safeword out of the session when the ropes are not done safely on me)