No one can know how far this falling down will be stop since bitcoin price are unpredictable but my own prediction it will go down to $6k and then pump up again to $9k to 10k.
In the case of ethereum the price also falling down but this downtrend is the best opportunity to buy more since ethereum reach $1k + and for sure a little pump up can give you a good profit Im also planning to buy more ethereum and hold to my wallet.