If you want something to help you feel comfortable and relaxed, try marijuana! I know most places it's illegal but it really does help. If you want something less potent, try Kava root. Polynesians make it into a drink. there is kava tea. And I know there are also capsules. Also look into Kratum. It is very good.
Caffeine does not make you more comfortable and relaxed. Instead, caffeine does increase alertness and wakefulness. It as well fastens your thinking and as well increases your focus and gives your body a better general body coordination. Read more; http://svmsl.chem.cmu.edu/vmsl/Caffeine/Caffeine_effects.htm.