I am 46 years old and I have been getting my period every 2 weeks. It lasts for 4-5 days. This has been going on since I had surgery in 2008. I become very tired. Every now and then, it feels like my heart is racing and I become out of breathe. I have been taking iron supplements which seem to help. However, they make me constipated. I have been to the doctor, but received no answers. Any suggestions? I am a 46 year old female, weight: 162 lbs., am 5'2".