I feel a lot of relationship anxiety, What can I do to help?

I don’t know why, but I feel a lot of anxiety about my relationship. We’ve been going out for 8 months, and I ought to feel secure, I have no reason to NOT feel fine, but for some reason, there is a small, minuscule situation where I think I might have offended my boyfriend or I might have said something in a bad way, and I become very sad. For example, I say I find a favorite show of his boring, and he asks how I could find it so. I become very sad. When we first started going out, I constantly questioned his feelings, is this something along those lines?