How to get to the root of (more subtle) suffering?

Hello, everyone! First of all, I want to say that I am not a user of the WU app for certain reasons. Please don't kick me out, lol :))). It's just that this subreddit is the most adequate among the other "spiritual" subs.

So, I've been meditating for about a month now, mostly focusing on my breathing (20-30 minutes of practice), and I'm trying to be mindful in my daily life.

Before that, I spent several months studying the teachings of Nisargadatta, Balsekar, Adamson, Wheeler, and other non-dual teachers, mainly from this tradition. I came to meditation because I realized that I couldn't get to the root of suffering and fully understand how and why it arises just by reading books - I simply lack the attention skills...

So far, there has been no particular progress (of course, I'm not going to give up, I understand that a month of meditation is just not enough to develop the skill.) Anyway, suffering still "just arises," and I cannot notice/recognize what thoughts cause and accompany it. It feels like I just feel unwell/anxious for no apparent reason.

However, I do notice thoughts if the eвmotion is very "loud." For example, it's more or less easy to notice thoughts like "I'm so stupid, why did I do that" (which, as I understand it, are a manifestation of the idea of personal doership/belief in self/free will) that cause intense shame. But I can't figure out the cause of the constant subtle/suppressed anxiety and dissatisfaction, I just don't notice what I'm thinking about. However, I am sure that I feel this suffering because of my thoughts. All teachers point to this, including Sam Harris, who talks about it a lot, and so far my experience has confirmed this...

So... How are you guys doing with this? What helped you recognize the cause of suffering? So far, without a clear empirical understanding of the mechanism of suffering, I have not been able to make any progress toward freedom from it, so this is very important to me.

In fact, I'm just looking for inspiration, because it feels like I'm banging my head against a wall. I just ask myself: why am I feeling bad right now — and I really can't see it. I just experience constant subtle emotional discomfort seemingly for no reason...

*I wrote this post using an online translator, so sorry if there are any mistakes.