menopause & HRT

I have not had a period in about 25 years and been on HRT for about 20 years.   I have never had a period during that time.  Many of the years I was on Estrace and Provera.  I was then changed for about a year to Prempro.  I moved and changed MD's again.  She put me on Enjuvia and 14 days of Prometrium every 3 mos.  THis last checkup last month, I complained about the expense of these two drugs.  She changed me to Estrace and Provera for 12 days/mo.  On day 11 of Provera I spotted a small amount.  Day 12 & 13 I have full bleeding, sloughing, lower abdominal cramps just like the "old" periods I had years ago.  This does not seem normal to me and I am concerned that the change in HRT caused this.  I do plan on calling the MD to see what she recommends.  What is your recommendation?