When to test if I'm so irregular?

I know its going to be negative I can feel it it's always been like that since March. To be honest I don't know when my period is due because I'm so irregular didnt even have one for 3 months. I was put on bc on November 11 to regulate them but didn't like them stopped in the middle of the pack the second week. I don't even feel pregnant. The green marks the days I had sex I don't even know when I ovulated people keep telling me just test but I don't wanna see another bfn :( Last test I took was blood November 4 negative.