the drugs doctors precribe for ADHD (with or without hyperactivity that is!), are methylphendiate (ye olde Ritalin) and dexamfetamine (Dexedrine).
There is a newer drug on the market (atomoxetine), but it never really caught on and is not as effective as the older stimulants.
Caffeine is not a stimulant that works in the same way as the drugs dexamfetamine and methylphenidate (which prevent dopamine and noradrenaline reuptake / block MAO temporarily [for those that want to know!])
caffeine does not work in the areas of the brain that are targeted by the two drugs for use in ADHD. Nicotine will not help!
You should speak to your GP.. in most cases he will refer you to a specialist who is familiar with the diagnosis and use of drugs. If it is serious enough (which i think you agree it is), then you may be put onto a low starting dose of methylphenidate (about 20mg per day) which can be adjusted to you according to your response.
let us know how it goes!