Why might Metta's emotional focus overwhelm my racing thoughts and anxiety?

My anxiety is in the form of unstopping, racing thoughts and overthinking. I also read that Metta stimulates the growth of feelings, which may be excessive to my already overstimulated brain. Is concentration-based meditation really safer in controlling my condition, or is the effective practice? My name is Neha, born on 25th October 1995. Time: 11:05 AM. Location: Lucknow.