"What can I do when I feel like I am barely coping, and about to have a panic attack?"
You need to know this: the only way out of your maze is to Be in the place where you are.
If you are barely coping, here are the instructions for you at this moment: barely cope.
Barely cope, but do not compare yourself to anyone else, and do not compare this moment to any other moment. It's the wanting to be elsewhere that causes you to suffer.
Barely cope, without resistance, without comparison, and your bare coping is suddenly full of Presence.
This moment of barely coping has the same fullness as the most wonderful moment! The content of this moment may be different, but the Presence is always the same; it is boundlessly complete because there is no other moment.
"But what can I do about this panicked breathless sensation in my chest when I am barely coping"?
Instead of avoiding this panicky feeling, feel it 100%. Commit to spending the next few minutes being with the sensation as it is. This is your path out of the maze.
It sounds obvious, but it may come as a revelation to discover that you feel breathless because you are not breathing. When breath is constricted, you will undoubtedly feel panic, because this sensation is how the body tells you that you need to breathe. Your body is your spiritual guide.
Just becoming aware of your breathing, instead of trying to focus on something else, will gradually slow the panic response. Stay with the breath and merge your mind with every physical sensation as it arises. Then, when you are ready, take one slow marvelous breath, filling your whole body.
Amazingly, millions of people have never completed a single breath, from the nostrils right down to the belly. Do it now. In the midst of a panic attack, this breath is your only duty. Savor every inch of your breath-body: the cool sensation of inhalation in the nostrils, the brush of air with the sound of a breeze down the back of your throat, the slow expansion of chest and ribs, the softening and widening of your belly, and the sense of touching bottom, grounding in the pit of the stomach. One breath can be the path that connects heaven and earth.
Now breathe out, following this same path in reverse, from belly to nostrils.
Yes, it's a hectic day. So what? It's the only day you have. In fact, it is the perfect day because there is no alternative. "This is the day that the Lord has made. We will rejoice and be glad in it." (Psalm 118)
Even in the middle of a hectic day, you can celebrate this breath, this moment, this body.