The very first time that Volume in down movement is greater than upward, it means we are ether in pullback after PSY, ST(A), or ST(B). All in all, it means we are close to the end of the uptrend.
After that, we will see that the movement to the down has more volume than up movements.
After confirming the horizontal TR, we should wait until continuation or reversal of the main trend reveals. After that, one of the best indications for continuing our bias is to watch how price reacts to the parallel trend lines which described above.
As we see, We are in phase D in weekly timeframe. Because of that big bearish bar, it most likely the downtrend will continue to one of the resistance levels. So for long term investment it's better to wait for the BU to continue uptrend.