There are two schools of thought regarding edits of posts.
One, is people might edit and change the entire meaning of the post, after others have posted in rebuttal or comment. That is bad form.
Two, is people should be allowed to correct inadvertently wrong or poorly expressed (including spelling) posts.
The ideal, of course, is some happy medium. I think 30 minutes is common but I suppose 15 minutes is at least somewhat forgiving.
The problem I see with the limits is people must create a post in a window of limited size (in the case of BITOG, 10 lines tall). That does not allow someone to see "the big picture" in a post, so he or she is required to post it, then read it for errors, then correct them in the allotted time. I always check for syntax and spelling so I almost always edit a post after posting.
I don't use automated spelling checkers as they are pure [censored], changing the meaning of words when they should simply correct spelling only. But like all computerized applications, they are as dumb as sticks and can only do what their programmers tell them to, and programmers can't spell either. So it's a problem. Still, it's not onerous and I can live with it.
The good news in this is the OP will probably remember the lesson and no longer make the same error, or do as so many people do and post their eMail addresses online. So all good, then. Remember that everything you post online, every eMail message you send, every text message you create, and every phone number you dial is recorded and kept forever, somewhere. So don't post/text/create stuff you would not want sent to your wife or read aloud in open court, and you will be fine.