We've all gone to the doctor or to Emergency only to be told our symptoms aren't anything serious. I'd guess the vast majority of medical visits aren't actionable (ie, no prescription, no stitches, no tests run), so why do we feel so embarrassed when it happens?
Part of it is the mixed message we get. We're told not to wait, to come in early, to trust the doctors who have the medical training to figure out what is serious and what isn't. Then you get to the actual doctor, who is a human being and will show irritation if he or she thinks their time is being wasted. I've actually called one or two doctors on it, reminding them that they have the training and I don't. (Didn't really help anything, except my pride.)
I think this is a part of parents' reluctance to go for testing when they suspect something is wrong developmentally with their child. We get so used to being diagnosed as "overanxious parents" rather than respected for our concern that it feels more like an opportunity for humiliation than early intervention. (The other big part is that we don't want to believe there could really be something wrong. Every child is supposed to be born perfect, after all.)
Add in the ignorance of many family doctors who push parents to wait and dismiss their concerns, and there are a lot of kids who aren't getting the help they need during the perfect window for it.
I'm biased towards getting early testing and early intervention. I'd rather look like an idiot than miss something. Even if it does hit me in the ego sometimes.