Used a vibrator toward the end of my period and saw a massive blood clot. should i be concerned? size of a 50 cent coin.

CLOTS WITH MENSES: CLOTS DURING AND AT THE END OF MENSES REPRESENT BLOOD THAT IS POOLING AND CLOTTING SLOWLY. CLOTS ARE NOT ABNORMAL DURING MENSES AND THE USE OF A VIBRATOR DURING MENSES IS NOT CONTRAINDICATED. THE CLOT MAY REPRESENT POOLED BLOOD THAT DID NOT FLOW VERY QUICKLY. THEY CAN BE AS LARGE AS 50 CENTS PIECE NORMALLY AT THE END OF A CYCLE WHEN THE BLEEDING SLOWS DOWN.