Seems you have left some rubber longer than the end of the blade so maybe you hit the table from the inside out of the rubber whithout the blade touching the table.Only the rubber which sort of cracked.
I boosted after six months of use with seamoon and the result was a livelier rubber with better speed and spin as when it was new.Since they are quite cheap If i buy them again i will boost from new.
Being a doctor i can tell a good therapie. Others do substances i prefer pinpon for that.
So hi to everyone from my living room and merry christmas to all EJs.