It's ok. Just because you messed up today, doesn't mean you will in the future. Don't get mad at yourself, but instead try to look to the other side. Because yes, there is another side.

One time a few years ago I had a horrible day. I was trying my hardest to fight the urge and so I thought that being alone in the bathroom might help. Well, I went into the school bathroom and found...a random open safety pin! I shook for about two minutes and contemplated what to do when finally I made the extremely hard decision to flush it.
Next time, try flushing it. It won't completely get rid of the urge, but you will feel SO proud of yourself afterwards!
Good luck, dear! I know what it's like, the withdrawals and everything, but you are strong enough to do this!