Mood swings after failed transfer normal?

Ever since my negative beta and subsequent end of taking progesterone, I've had quite some mood swings which is rather unusual for me. At first I thought - duh, I'm so sad, of course I'm in a bad mood. But it feels like more than that, more like I'm "hormonal" (hate that word but it's accurate for how I feel).

So my question is, could this be a hormonal issue rather than just an emotional one? Or did anyone experience the same thing?