2) see above, under 1) - perhaps your light source is too strong?
You did not say what kind of enlarger you are using (condenser, diffusor).
Perhaps you are missing a diffusor glass? Some enlargers have a diffusor glass plate between the light source (lamp) and the lens, which you might be missing.
Just an idea...
Then again, if you have used that enlarger before, you probably know how it is supposed to be used And the light source should not have become brigther during the year you haven't used it