No, not at all. Can you still go into STEM if you aren't as gifted in math and science as others. What you lack in innate talent will be far outweighed by your EFFORT!
Not really, you can still study. For me, even if you are not that smart in that kind of subject, you can and should study that for you to be good at it and my advice is don't pressure yourself to just do what you really want.
