"When he puts forth all his own, he goes ahead of them, and the sheep follow him because they know his voice. " John 10:4 (NASB)
My admittedly limited understanding, is that in the Biblical setting, they practiced "open grazing", which is best for small livestock, because instead of fencing them in and working to try to keep the ground continually producing what they need, you move them around to where what they need is growing, leaving the grazed ground to [...]
Why would a shepherd need to "gather lambs"? What is it like to gather a new lamb? Did you ever consider that when Jesus, your Shepherd, gets the chance to take care of you in your need, in your place of vulnerability, it may actually make Him feel good?? Carrying you thru your difficulties is not a chore to Him, it is gratifying, because He loves you! He likes to hold you close.