I have not had intercourse for almost 9 months. I am using a MIRENA IUD, which I had put in in April of 2009. Since then, my periods turned into only spotting for a few days. Nice. But, I have had sex this past month, and since then, I have been surprised with bright red bleeding, which is moderate. I have not had such a heavy period in at least one year.
As well, I have lost 8 pounds in the last 6 weeks, due to stress, I assume. And finally, I just noticed an enlarged inguinal lymph node.

Should I be concerned? I am concerned about the irregular bleeding. Any explanation?