Hi Maria,
The active ingredient in alli is orlistat which works by inhibiting the fat digesting enzyme lipase. It is minimally absorbed by the body and has no systemic effect which means it does not affect the central nervous system, the heart or the brain. Alli has no lasting residual effect once it has been discontinued. The symptoms you are describing are not associated with all and are not something that will develop after months of use.
What kind of vitamins are you taking? Vitamins are supplements, they will not cure you. Some formulations contain herbs and other ingredients that are high energy which can affect the body (insomnia, palpitations, upset stomach).
Even though the symptoms have gotten better, they are still there and should be checked out by a physician.
Your health is of utmost concern.
Sophia De Monte RPh