Well she did have practice swinging around her stick, and lightsabers are pretty much the same thing but glowing and deadly. The tactics would be similar at least.
Latest movie had too many plot holes. SPOILER: if they could have just rammed the fucking ship into the mothership then why not just send a bunch of small battering rams at light speed at the first order. Made the whole point of the movies pointless.
THERES NO EVIDENCE AS TO HOW SHE ACQUIRED IT.