If Krishna is pleased, you will feel pleased. This is automatic. If you are not feeling happy, that means Krishna is not happy by your service.
“Sa vai pumsam paro dharmo”, Unless we get pleasure, we can’t do it
Bliss in bhakti comes only when there is eagerness to hear God’s messages and this eagerness comes only when there is a sense of urgency.
Spiritual life is not dry, it is also exceuted happily, 'susukham'. The result of that is not just happiness, but bliss, spiritual joy.