9/10 DPO Cramping

I keep cramping only on the left side, then a little in the mid section then back to the left, I tested this morning knowing I need to wait but I'm so impatient got a BFN, I got this left side cramping on Sunday as well, has anyone experienced this at 9/10dpo? It feels like throbbing cramps, like its tightening then loosening..that's the best way I can explain it, anyone?