If you are having trouble during certain times over other than it sounds like there is a common stressor.
Are you at work or class when these feelings happen?
If one or more strike you with specific individuals then something about them is triggering the response. It can be a multitude of things and hard to pinpoint a specific.
Therapy does help I find, even if it takes decades. We are not made in a day and it takes even longer to unmake us without destroying ourselves.
This one I understand the most. Sweetie, you are valid as you are, first and foremost. I deeply know the pain of staring at my hands and knowing they are not what they should be. I know what it is to see your shadow and have a moment of fear because you don't see it as your own. You are worthy of life, of respect, and of love.
I want to state that it sounds like you should talk to a gender therapist that has the medical knowledge and training to guide you better than we can.
Would it be overstepping to ask what about your bi/pansexuality makes you uncomfortable?
And to answer why at least I am seeking out HRT and SRS, it is because I feel it would help me better present the person I am to the world rather than have to act as an individual I am not.
While I may not like the body I have I can do what I can to make it more comfortable. And for the things that like height I lean into them. While I wish I was like my sister at a nice 5' so my lover could tower over me I just have to be a tall queen than act like she is 5'.