Clomid & early AF?

I was wondering if anyone has experienced what I'm going thru right now. So I'm on my first cycle with Clomid. I took it CD 4-8 and I ovulated on CD-14 . Yesterday on CD 18 i started cramping and sort of spotting. & today CD 19 I'm still cramping and I'm not spotting like yesterday just very little. Could this be my period 17 days early? If anyone has had something similar happen please let me know. Thanks!