22 dpo and bfn!

So I took my 3rd round of clomid, this time was 150 mg. According to my opk's, I ovulated on cd 18. I am now on cd 45. I have taken 3 pregnancy tests, one of which was this morning, all came back negative. I've felt like I'm getting ready to start my period for 2 weeks now, but nothing. I've had off and on cramping, mood swings, emotional, and sore nipples. Does anyone have any advice or have been through something similar??