I have Parkinson's & have just started to cut down on repinerole & have started taking Entacapone. Why has my tremor got worse?

ROpinirole. Dopamine agonists such as and especially rOpinirole are particularly effective for tremor. You realize of course that rOpinirole and entacapone do completely different things. Entacapone isn't a dopamine agonist; it is an adjunct to levodopa to prolong its effect. One drug doesn't replace the other.