premature baby

I was born premature, i was suffering of leukemia, so they transfuse me twice.
Now, I have a sort of tuft of fibers inside my heart (in the top) , and i can't express my feelings , all stay inside of me, is this a disease ?

[Cleveland Clinic]

I am not sure what it is that you are describing, but I don't think that this is at all related to your ability to express your feelings.  

[leoto]

it's a small ball of fibers (a biological matter) , like coton, it's goes up when i'm happy and down when i'm sad inside the upper part of my heart . I can't tell a word when i'm in love. This is NOT shyness. This is a alien substance. Have you ever seen that before ? Look inside the files about human experimenation or something like that. For me this is not natural.