After 2000 rep, you won't have this problem.
Below 2000, you aren't allowed to make edits without approval. So they go into a queue waiting for one of our fearless moderators to make the decision to approve. Usually, unless your edit is malicious or moronic, they're approved. It's a mechanism to keep spammers and vandals coming in and destroying the site. The very fact that <2000 users are allowed to edit at all, is recognition that you're probably helping out in good faith.
Now, suppose MegaUser10000 comes in and edits the same post you did, before your edit gets approved. The problem is fixed, and no further edits should be approved. But you're still waiting in the queue. The solution is that one of those two edits needs to win, and one needs to lose. Unfortunately, the one that was actually done wins, and the one stuck in limbo loses.
This is nothing against you or your edits. It's simply what works. Answer a few more questions and get the rep up, and you'll start winning the race.