I can relate to that panicky feeling before a supervision where you don't think you've got enough to say, or you feel that you haven't worked out how to say it coherently. But I'm sure you've got more to say than you think, and you might go away having learned something new. Sometimes a chance throwaway comment from my supervisor has really made me think about my ideas in a new light. And even though deadlines can be a source of stress, they can help to focus your mind and your ideas.
I think it's important to have regular contact with your supervisor, even if some meetings are quite brief. My supervisor seems to be avoiding me: we haven't met for 3 months (which isn't untypical) and I find the lack of structure and direction quite difficult. In my experience, once you stop having regular scheduled meetings (as I did in my first year) it can become difficult to pin your supervisor down and get the contact you're entitled to.