Hi,
First, Good job on the GMAT. When I took the test on Aug 2 a few weeks ago, I scored a 700 (90th percentile, and 44Q/41V split). So, I am the person you should be fuming at

(just kidding). But I DID actually score a 700, 44Q/41V, and I have some insight for you after living with my score for a few weeks now.
I highly doubt any school is going to turn down an applicant simply due to a 690. If they do, it's probably not a school you really want to go to. Most top schools have that 80% range from about 650-750, so a 690 is still in the middle. Quantitatively, 88% is only 2 % away from the 90 percentile. It's still in basically the same area, and most people realize that the scores have a normal variance of at least 30-50 points depending on lots of factors. So, in terms of intelligence/ability, a 690 is virtually the same as 700.
Where you got shafted is how a 690 FEELS compared to a 700 when a human being looks at it. A 690 feels a lot less than a 700 even though it's only one notch down, since everyone has been programmed to look for "700+" as top tier. Conversely, iin a cruel twist of the universe, a 710 does NOT feel different from a 700, even though it is equally distant by 10 points.
To add insult to injury, you had solid scores overall (46/39, very similar to me), but you narrowly missed the coveted 40's balance by just a point. So, your overall score combined with the breakdown looks worse than it is. To the HUMAN eye, your score does not feel significantly different from someone who scored, say, a 670 or 680 with a 43/37 split, or whatever it would be.
So, basically, the GMAT gave you a solid score good enough to not keep you out of most top tier schools, but it shafted you by withholding the full weight of the score.
The problem is, if you retook the test, you assume massive risk, and don't stand to benefit much. Let's envision some scenarios for you:
1) You retake and get a 660 or lower. It can happen! You have gotten lower than this on some practice tests, so it's definitely a possibility. Not only would this look bad, but it would confirm to the adcom that your original 690 was not the low end of your scores. A downtrend is always bad. FAIL. At least with your 690, it looked like your score could have been anywhere from 660-720.
2) You retake and get about the same as the first take, a 680 or 690. So you wasted money, time, and are forced to apply round 2 or later (if you wanted to retake again... or would you at that point?). Not only that, but it would look weird to have taken the test and gotten the same score, again below 700. It would confirm to the adcom that you were WORRIED about admission with your original score, and still couldn't produce even after making another attempt. Retaking a test says a lot about your confidence and comfort level. Adcom would know that you are applying with a score you don't like. FAIL
3) You retake and get a 700 or 710. You break the ceiling and get the number you were seeking, but you delayed your application and had to take the test twice to achieve it. Not only that, but remember that quantitatively you have not improved much. You're still in the 90th percentile-ish area. One would expect your score to increase significantly on each retake, and it didn't. This would be a diluted, unimpressive 700+
4) You retake and get a 750+. This would be great, except it could be difficult for you. It would likely require an unreasonable amount of studying to achieve this. The GMAT was not intended to be a life goal you work on for over 6 months, it is intended to be a quick test of your current ability just prior to heading to b-school. None of your practice tests indicated that you are at this level, and your first take confirmed that. So even though it would look great on your app despite a retake, this is a low probability score for you. Your time and effort is better spent elsewhere.
The probability of the first two is greater than the second two, and carries enough risk to deter any reasonable person from retaking. With a 690 you lost one of the battles but still won the war, which is what counts. By only taking the test once, it shows the adcom that you were comfortable with your score and only needed to take it once, which looks good on an application. So, you should live with your score and focus on your application.