Un - triggered moments of anxiety. Help!

I am suffering from untriggered moments of anxiety where I have feelings of self doubt, lack of confidence, nervousness together with physical symptoms like slight heaviness in breathing and sweaty palms. For the last 8 of years my  career is not doing well which I initially thought is the main trigger for my lack of confidence. I used to drink frequently till last year and the next day I would have feeling of anxiety and fear. I had trouble sleeping as well. Since then I started exercising and lost 8 kgs and got back in very good shape, cut back on my drinking. I have also done some substances for sometime a couple of years ago but now I have totally stopped. Since the last two weeks I have been facing anxiety issues without any reasons, without drinking, and exercising regularly which was not the case earlier. However my professional life is deteriorating. I realised today that there is smethjng wrong when I accomplished a professional feat but still got anxiety attack. please help