I get this all of the time. Sometimes I'll even get my nerves wrapped up into such a tizzy I think it best to ease my way into hyperspace, with a light sub-breakthrough dose to prime myself for the real deal. Before I've even exhaled that first hit, as soon as the initial physical effects begin to make themselves known, I'll almost always get very very comfortable and think "Ahhh, forget that let's just go all the way."