Can't react on second forehand

before I trained I could not do forehand at all 

after I can do forehand close to the table and slow balls but almost always the ball is fast to forehand then I don't have time to do the move and block forehand 

i guessed i should move back but when i do this my backhand becomes so slow

any tips to have time to do forehand topspiN?

Hi Felix,

You can think about being more balanced for each stroke.  Perhaps don't do so much with the first stroke if you are throwing yourself off balance and don't have time for the second.  Try to be a little more patient and play a stronger shot when you know you are going to gain the advantage in the rally.