From Doctors Health Press

The Side Effects of Splenda
Are artificial sweeteners bad? It really depends on who you talk to and which studies you read. The studies that are against sucralose show side effects from its use. Some of the more commonly reported sucralose side effects are:
Migraines;
Dizziness;
Intestinal cramping (3);
Rashes;
Acne;
Headaches;
Bloating;
Chest pain;
Tinnitus; and
Bleeding gums.


It mentions bloating, and maybe that is connected with fluid retention?

I any case, you are on the right track and eliminating the Splenda couldn't hurt. Best Wishes.