Mood Shifts (Not Thought Related)

I’m new to Scholars, and still trying to wrap my mind around the idea that thoughts create feelings. For the most part, this makes complete sense–I’ll encounter a situation, have a thought about it, and then feel a certain way.

But, there are also times when my feelings seem to be generated by something hormonal/chemical. I have the feeling, without a thought attached to it, and instead the feeling itself seems to generate lots of negative thoughts, and then just lifts, also on its own without conscious intervention on my part. Like a cloud passing over me. Maybe the C, in that case would be “depression”? Can the C be a feeling?