Picking Which Urinal to Use

I had an interesting dilemma the other day. I had just drank a dangerous amount of shasta, and felt as if my bladder was going to burst. I ran to the nearest washroom (this was at a small local movie theater). As I walked in there were rows of stalls in the back, all taken. There were two rows of urinals, one to each side. In each row there were five urinals and the row to the left was full, so I looked to my right. Out of the five urinals, two were taken, in a way like so:

1_____  2_____  3_____  4_____  5_____
|taken| |     | |     | |taken| |     |  
|     | |     | |     | |     | |     |
|_____| |_____| |_____| |_____| |_____| 
\____ / \____ / \____ / \____ / \____ / 

Now we all know that the rules of washroom etiquette are the most important unwritten laws for men, and you must make sure that your other washroom users don't feel uncomfortable in about any way, so I had to pick very carefully, but I was running out of time. I decided in a few seconds (trying to look like I wasn't trying to choose) to choose number 2 because either way I would be next to another user. But number 4 promptly left, and I was left smothering number 1 in the corner, looking very awkward. I had broken the rules, but since 4 left so quickly I still had a chance to move! I had already chosen my urinal, if I moved could that rectify the situation? Or might it worsen my situation? I decided that since I had already broken the rules, I had nothing to lose, so I quickly jumped to the next urinal over and mumbled gibberish so no one could hear.

I did worsen my situation. It was a mistake that I shall regret, for I know that inside the hearts and minds of the others in that room that day, I shall be banished forever. Please learn from this.

Update, Nov. 1:

Thinking about this again, the true proper way for users to fill the urinals would depend on whether there were an odd or even number of urinals. Even there were an odd amount, for example 5, then they should be filled in way so that no one person fills the spot next to a person who just got there, like so:1,3,5,2,4. Or if it was nine, then:1,3,5,7,9,2,4,6,8. This way, it would take two people leaving at the same time to disrupt the formation. This would follow FordPrefect's principle.

If there were an even number of urinals, then they should be filled outwardly then moved in, so if there were 6, then they should be filled like so:1,6,2,5,3,4. Or if there were 10, like so:1,10,2,9,3,8,4,7,5,6..

It may be hard to count so fast, but you could probably just tell just by looking.