Katie, I retested after 3 months, but from what I've read the effects should be within a day or two (and reverse just as quickly).
I take one with breakfast (mid-morning) and one with lunch. Haven't had any of the hyper side effects. I think that would imply that a person is just pushing the conversion back to methionine too hard, making more if it available to make SAMe. People that complain about being hyper might just be taking too much.
That said, I always titer up any supplement slowly to monitor side effects.
Lucy, try increasing your P5P (shoot for 40mg) to help that CBS variant. And if that doesn't budge it, try adding some riboflavin - it's a co-factor in a few places in the methylation cycle. And if all else fails, go up another notch on TMG. It took 1 g/day for me to get below 8 where I was stuck at the 750 mg level.
Also, as Katie mentioned, check your zinc levels (not the most accurate blood test), but if you're in the low range, then you're probably low.
Hope this helps, from "the homocysteine whisperer"