It's strong enough to measurably increase your metabolic rest rate and consequent calorie consumption even without obsessive foot tapping.

Also, the foot tapping behavior can be related to caffeine consumption even if you also do it when not taking caffeine. Some people (like me) metabolize caffeine a lot slower than average, so its effects last a lot longer (twice longer or so, I think). Also, caffeine notably causes sleep disruption. And caffeine withdrawal can also cause irritability.

Caffeine can also increase anxiety or anxiety-related behaviors, and even if anxiety or these behaviors are not exclusively experienced while taking caffeine, it can still increase the likelihood and magnitude of its effects. These behaviors can also persist in the absence of substance intake for a variety of (psychological) reasons.