If I am stunned with Stellacorn as the attacker and get pushed back to base, does that count as a move and I draw?

No, your Stellacorn Herder will not draw a card in that scenario.

According to Rule 450 and established RiftJudge FAQs (specifically FAQ #10124 and FAQ #10165), a Recall (the process of moving a unit back to the base after it is stunned or fails to conquer) is strictly defined as a game action distinct from a Move.

Because Stellacorn Herder's ability ("When I move, draw 1") specifically triggers only upon a Move action, it does not trigger when the unit is returned to the base via a recall.

Summary:

• Recall vs. Move: The game rules define these as separate actions. Being recalled to the base due to being stunned in combat does not satisfy the "When I move" trigger condition.
• Result: The ability does not activate, and you do not draw a card.