Unclear thought patterns?

I’m trying to process my feelings. I am currently sitting with a heavy feeling of sadness and anxiety. I’m trying to find out where is is coming from but I am not having any specific thoughts to determine the root. I am grateful and appreciative of my life. Just trying to sit with this negative feeling and understand it, but what do we do if we continue to do this and we’re not coming up with the answers?
I’m starting with the feeling..

C- ?
T- I don’t know where this feeling is coming from
F- anxiety
A- jumbled thoughts that are not clear. Feeling resistance but not sure what it is that I’m resisting. Can’t focus or relax.
R- sitting here unable to determine why I feel this way so I can understand it.

I know this is very vague, can you please help me?