Buy alt coin with bitcoin and both go up 300%, so did I even make any money?
Of course you profited, because your market value just increased by 300%.  

In your case:
You had 1BTC (worth $5000) on Monday.
You sell 1 BTC and buy 50 XYZ( 50 * $100 = $5000).
Then comes Tuesday, both XYZ and BTC goes up 300%.
Now your 50 XYZ is worth $15000, you exchange 50 XYZ for 1 BTC.
You see, your total market value increased from $5000 to $15000.