I feel you so much. I have migraines since I'm around 8 years old. Back then, in the late 1980's many doctors were of the opinion that children do not have "Headaches". And they told us so repeatedly.

Today sience has caught up on this fortunately and when my niece started to have bad headaches at around 9 years old, there were whole protocols of diagnostics and treatments available.

I was just lucky that my mom had awful headaches as a kid as well that went away with her first prefancy (typically for migraines to start or end with a big hormone change) and she never got diagnosed with migraines, but she still knew how it feels and that I wasn't faking for more attention as the doctors said.

I'm still unconsciously scared that doctors won't believe me and I make a plan before every appointment of what to say, so they will believe me. Its not rational, but I still can't shake the feeling.