What are the primary symptoms of excess caffeine and tobacco use?

Hyperness: Excessive caffeine may cause jitterness and hyperness and alertness. Sometimes a person may feel their stomach is bothering them and they may speak rapidly. Too much nicotine can actually cause a person to fall asleep and pass out. Lesser, but still high doses of nicotine can cause dizziness, blurry vision, headache and vomiting. Everything in moderation is generally a good guide.