Leaving a job and learning from it

I recently left my job after several months of feeling undervalued and frustrated. After months of having received a promotion, I realized that I was being paid below average. I felt disappointed in myself for not having done my own research and realized that I had to advocate for myself moving forward. I brought up the pay issue up to my supervisor after my performance evaluation and asked for my compensation to be evaluated based on the additional responsibilities I had taken on and the average pay. I was told that they’d be evaluating the pay and providing me with a raise after they secured additional funds. I was comfortable with this response, until the company received additional funds, but they delayed moving forward with the raise for over a year. I felt undervalued and frustrated that the increase in pay that we had discussed wasn’t moving forward. I checked-in on the issue every few weeks and was usually told that “they were working on it,” but from the months that passed, it seemed apparent that they weren’t moving forward with it. I then decided that if the company wasn’t going to value the work I was providing, then I would have to take it upon myself to find employment that met my pay expectations. I changed the circumstance and I felt so empowered to direct my professional growth, until I learned about SCS and the idea that it may be best to focus on changing our thoughts rather than our circumstances, which brought me a sense of shame for having left my job. I want to process this experience and learn from it to ensure that I am not repeating a pattern of trying to change my circumstances. What steps can I take to be curious about these past actions to learn from them while being compassionate with myself?