Am I dumb for not understanding Shakespeare?

I’m 20 and I've only recently started reading Shakespeare (English isn't my first language, so I'd always been scared of reading Shakespeare). I've read Hamlet and Romeo & Juliet so far and am in the middle of the Taming of the Shrew. After finishing each scene, I chrck out some commentary on it provided by cliffnotes and other sources. Sometimes they point out some things that I didn't have the slightest idea could be interpreted that way. Am I dumb for not understanding and noticing them sooner? Will I ever get better? Is there any way to improve sooner?!