Those are some scary symptoms. What sweetener were you using the most? Out of all of those I think aspartame is potentially the most dangerous, but I don't consider Sweet n' Low to be bad at all.I totally agree with these statements SJ.
For the last 2 years I have been addicted to Diet Mt. Dew. I started cutting the carbs 2 years ago and figured that Diet Dew, and Splenda, and Sweet n Low, and the rest of the fake sweetners was the way to go. Let me tell you about what has happened to me since I did that. First, I started having bad headaches and short term memory loss. I know I am getting older, but the memory loss came on about the time that I started putting the fake sugars in my body. I did some research and lo and behold they have found that the fake sugars do cause short term memory loss, and headaches. So, for the last week I have weened myself off of them. I like a little sweetness in my coffee and so I discovered Stevia. It is all natural made from a plant. It is way sweeter than sugar and a little goes a long way. A friend of mine told me about it. You can get it at Health Food stores. If you use to much it tends to have a slightly bitter taste, so you have to experiment to get the correct amount for you. OH, and I really like carbonated sodas, and I don't want to drink the high calorie real ones so here is what I did as well. I got me some sparkling water and some unsweetened Juice and put a little Stevia in it, mixed it up and made my own soda. It actually is pretty good. OH, and I do the real butter, real sour cream, real cheese...just in moderation. I have learned that is the key.
I drink aspartame (and sometimes sucralose, aka Splenda) in moderation, like 1-2 cans of diet soda a day, and I don't think it is harmful in that amount. But when I hear stories like this it does make me reconsider.