I'd say muscle tension is the culprit here, along with a hyper attention to what you are doing as a result of SA. Good news, as is the case with almost every obsession or anxiety related "concern", other people hardly notice the "enormous" problem you think is so evident. Even when they notice it, they don't care.
I don't look at a girl who for instance may have an acne on her face and judge her for it, start discrediting them as a person. I don't also think she is ugly, I don't care, my brain doesn't process such insignificant things, the environment has too much stimuli. Meanwhile, if this was an obsessive or anxious girl, she would be thinking every way I reacted to her was due to the acne. Same concept applies with worrying about *****ing walking.
"Rules are only limitations that you have placed upon yourself"