Love of God is the real source of happiness and when one abandons that loving real relationship of God, he suffers.
Knowledge will manifest as the realization comes. No need of becoming a pandit. Just as if we want to see the sun, we just need to open our eyes. The blind can't see the sun.
To be in ISKCON means to be in the association of devotees. If You remain in the association of devotees, Your spiritual life will be protected.
If we hear properly, the holy name will enter through our ears into the regions of our heart and shower down nectar. When we are lost in the ocean of nectar, we will see Krishna.