I had Mirena for 3 years. I didn't have the heavy bleeding, in fact I hardly bled if ever. However, I had many similar side effects for years.... irritability, body aches, cramping, breast tenderness. None of it was all that bad until the anxiety hit me full force 2 months before I finally made the connection and had it removed.
Your side effects seem tolerable, but watch for some of the more serious stuff....