Mirena (levonorgestrel) for about 6 months now.at night i feel like my heart is racing and it's hard for me to fall asleep,and feeling nausea, dizzy night sweats?

Mirena (levonorgestrel): It sounds like you are having palpitations or some other abnormal cardiac rhythm. I doubt this is related to the Progesterone in the Mirena (levonorgestrel) as it has been in for six months. If the symptoms have been present the entire time, i would remove it. Either way, the symptoms merit a visit to the cardiologist.