of course sell it, if you play the trading and intend to keep it for a long time, you might lose, it was I proved myself, but it's up to you bro 
It won't be profitable to sell it with current price, price is not the best at a moment, its better that we hold it for next few months, and sell it after the halving when the value of bitcoin is in better position.
Yeah, I think we should buy bitcoin at this price and save it for few months, and sell it after the halving, I am not sure about the mining part, so for buying, saving and selling will be more profitable.