did u measured how much was drained out of transmission. - did you also cleaned the transmission oil filter.
check transmission oil at dead cold in morning before key-in if oil level is higher [ over ] at cold mark means it is over filled, u may need to drain ONLY approx 200 ml from the transmission.
no need to worry there is nothing wrong, over filled can be drained and always be cautios.
over filling of transmission / engine oil is not recommended.