Im was exactly in the same situation as you, bought at the December peak and saw 20% or around 400USD wiped. I pulled out a few days ago, because I couldnt take it :D

When I get more free funds Ill go back in tho

As for buying altcoins - you can, you wont loose money on that particular transaction - the exchange rate between coins is what it is. During tough times BTC or ETH tend to hold their value more though, so altcoins are insanely risky right now

Best of luck and HODL