hello and welcome to HCM, Hematoma
is a collection of blood and it is dangerous only if it is either large or does not get resolved in a week or two.
Also the severity of Hematoma is dependent on the locality and cause
In this case it is very likely that you have caused the Hematoma when you tried to remove the tonsil
stone which is definitely not recommended.
You will be fine in a week or two but in future if the stones are bothering you then you may consider removing tonsils which will permanently cure you of your problems
take care and take anti inflammatory and antibiotic medication along with anti reflux medication
for speedy recovery without complications
Dr Sriram Nathan