While I think this might be unusual among most potheads, it isn't just you. Occasionally, I'd smoke some bud that favoured Sativas, and this would get my buzzed. I would be wired, and be able to interact much more normally.
Most of the time though, bud makes me sleepy. Introspective, relaxed, and tired. In fact, I primarily used it medically as a sleep aide for my insomnia. However, if you do sleep after you get stoned, it might be that you're sort of "conditioning" yourself to become tired after you smoke (even though it does naturally make you tired). However... I never thought that the effects I got from it were "normal" compared to everyone else. So I'd take in the words of those who are much more experienced with smoking different strains and noting the difference than I am.
Peace.
~Ethno