I suspect you may have had too much THC since CBD usually tends to protect the heart but too much THC can cause more heart symptoms and even hypertension. Maybe you should really lower the THC to a very low dose but consider trying a low dose CBD dominant tincture instead. You may just need more CBDs to calm your heart but start very low and slowly increase your dosage. Have you been using cannabis previously? Have you had this problem with your heart before now? Are you taking pharmaceutical drugs? You may want to do a drug to drug interactions screen.
Please, be certain you report your heart irregularity to your cardiologist.