Should I be using ovulation tests??

I see everyone on here using opk's, and I'm wondering if I should start using them. My periods are always regular (same day every month give or take a day).

So my question is: If my periods are regular, should I expect that I ovulate regularly as well and don't need a test to tell me?

I know you ovulate about 14 days after your last period (or something like that) and since my periods are always regular, my ovulation should be too, right? Should i invest in opk's anyway? I feel like they would stress me out even more.

Thank you!