Why don't I feel anything when I pray?

The beginning stages of prayer are us reaching out to God, and sometimes that may feel like reaching out into a void. That's okay. That's just the beginning. The point is that when we show up to pray, we are giving God our attention and allowing him to be God. God will always show up in his own timing. We don't need to rush that, and we don't need to try to manifest feelings. That is all delusion and fraught with dangers. We turn our time and attention toward God, and in due time God turns his time and attention back to us, although he is always listening.