Some thoughts... Can the clinic day not be rearranged? Is this the only day, or will there be others? If you miss this one, can you make it up later? Or can you do the exercises on your own after the WW walk?
If the WW walk is important to you, and that day is not the only clinic, I see no reason why you can't do both. Personally, I find it impressive - the idea of juggling both would stress me out. Kudos to you!
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Your Aspie Score: 138 of 200. Your NT score: 72 of 200. You are very likely an Aspie.
AQ score: 35.
There's a fine line between genius and insanity. I have erased this line. ? Oscar Levant