Molar pregnancy. Realtime complication?

Hi.. I had Molar pregnancy and had D and C on 2nd week of May month... My bleeding continued till 3 weeks, in that time span i was having regular Beta HCG tests... Initially I had around 1,00,000 values later D and C it got reduced approx to 50,000 then 30,000 then 12,000 and 4,000 by each week. Later by Yesterday I took Beta HCG again and it showed values around 11,000 which was quite shocking as i didnt have bleeding.. Immediately I contacted my Gyno, She asked to do USG pelvis scan, In dat we came to know the tissues has not been came out entirely, still there are very few tissues leftover.. I visited my Gyno and she started with stories like this can be Malignancy, we can check with MRI and take further call, also to repeat Beta HCG and I hav given for the test( MRI yet to be done, waiting for HCG report).. Is this can be true? Is this a Realtime complication? Im totally totally scared and felt like all my happiness has gone in a Minute. Plz suggest me.. I cannot accept it..