How do you know you ovulated?

I've heard people saying that you can have periods without ovulating. How do you know other than opks? I have ewcm for a few days during supposedly fertile week. I also have all pms symptoms every month. My cycle is 28-30 days. Have been trying for about 5 months but still no news.. any advice on what to do? Other than opks and bbt? Been taking folic acid for about a month now.