There is sorrow for sin and for the plight of others, but there is also celebration for what God has done and is doing. A congregation that doesn't rejoice in praise is simply not worshipping. It is in the act of celebrating and praising that it is easiest to feel the Holy Spirit. Sometimes, the Spirit acts while you're worshipping to reveal that which is holding out, blocking the Spirit from bringing about spiritual growth. The act of directing yourself away from yourself and toward another who is greater than you can be very revealing about what we're trying to hold on to.
Praise becomes a call to let it go.
In letting it go, the feeling can be like a fresh, cool stream flowing over you, as if bathing in God's love. Sometimes, the simple act of cutting loose in joy over God does wonders to strengthen one's faith . Cutting loose can refresh us, restoking the fires of our commitment and healing our exhaustion. Sometimes, getting lost in worship opens the door for the Spirit to break down certain fears. Like, the fear of being seen by others.