Why do i get giddiness while trying to meditate?

Giddiness: This depends on the type of meditation you're doing -- which i don't know. For instance, if using rapid, deep breathing in meditation you could hyperventilate and become dizzy ["giddy"]. Or, you could be sitting in a position that constricts blood flow somehow [crossed legs, etc]. For some people, meditation can be difficult because they rely on external orienting stimuli to feel grounded.