Sam just stayed in his cave and took care of himself. There really are some changes and one of them is that when he saw his friends a part of him wants to take a bite and suck their blood. But the instinct is extremely faint so he could control the urge.
In fact it that urge is dominated by the rest of his bloodlines so much that the feeling is extremely faint and negligible.
He could feel that something bad would have happened if the beast bloodlines are not present in his body.
He even conducted several experiments like taking some blood of his friends to keep in front of him, smelling it, and even applying it on his body, even though the urging increased it is within his rational limit.
Only then did he feel relieved.
