If to invest in some risky projects, play in margin trading or won’t be enough patient to wait till the growth of the coin even 1 000 dollars won’t be enough. In fact you could have invested those 900 dollars you’ve lost in Ethereum or in BTC during the correction just to hodl them and to be in pluses now. But it’s nothing to regret. You’ve got an experience and won’t again make such mistakes. Maybe trading shorts is not yours, try long-time trading in BTC, this is the simplest way to get profit.