Caffeine can make people jittery and cause fast and sometimes anbormal heart rhythms. It sounds like you should stay away from caffeine. Reasons to seek a doctor would be if you are having passing out or near passing out episodes, palpitations, or if there's a history of young people dying suddenly in your family.
The total duration of treatment depends on the complexity of the treatment and is generally comparable to that of traditional braces. Typically treatment can last between 9 and 18 months. During your consultation, your Invisalign Provider can provide you with more detailed information.
Lingual braces are the same as traditional metal braces, except that the brackets and wires are placed on the inside of teeth. Invisalign consists of a series of 18 to 30 custom-made, mouth guard-like clear plastic aligners. The aligners are removable and are replaced every 2 weeks.