I don't want to be rude because you are being helpful, but mindfulness is not the answer to everything. Mindfulness made me even more anxious because what I really needed was to see a psychologist.
A few years ago, I delved again into meditation, this time more traditional Buddhist ones. I can't say emphatically enough that there is some deep knowledge there. Mindfulness (i.e. cultivating stable attention toward internal & external stimuli) is just the tip of the iceberg.
Like you, I found the expanded sensory stream provided by mindfulness training to be somewhat overwhelming. Imho, what's necessary to work with it fruitfully are: 1) developing the capacity of non-abiding, or not attaching/identifying too much with the flow of mental events, 2) training the unconscious mind to competently manage one's attention & awareness, so that you don't have constantly "pilot" your self.
Two books I've found indispensable are: The Mind Illuminated - John Yates, and The Rinzai Zen Way - Meido Moore
Of course, there's no substitute for a good teacher. Just be aware that there are many charlatans & New Age types who aren't so helpful. Good luck!