You had period followed by Depo Provera. You need not think of the pregnancy. Little spotting could be due to the delayed waning off of Depo Provera. Depo Provera is Progesterone. When its levels go below certain levels, the lining of the uterus breaks and menstrual bleeding starts. Since it is oil based, it takes longer time to get released and get cleared from the body. Hence little spotting later on also. The cramps you are getting may be again due to Progesterone. It is known to cause muscle relaxation which can give rise to cramps. I hope your queries are solved and you are relieved of the stress of pregnancy.