I feel like I am very stupid?

I feel like I am very stupid and mental. The reason I say this is... I didn't even know words like larder, Medevac, Biannual, Commiserate, Biped etc. I am in 11th grade, and I had a medical condition that swooped over me and ruined my learning for a lot of years. I am about to p high school though.. and I am taking 1-2 years before college to blitz learn things I am supposed to know. Do you all think I am stupid if I don't know those words in 11th grade? Am I hopeless? I want to be a doctor... and I can't believe I am this far behind. Whats your thoughts?