What I recommend is all that, plus a heater pronto! It's a real shame, but as you have probably already found out, pet stores will tell you anything to make a buck. Could you imagine how their sales would drop if they told people that bettas need all the conditions of a regular aquarium fish?!
This care sheet is a good place to start: http://www.fishforum.com/betta-fish-...are-faq-20058/
PS. I had my Lou in a bowl in college last year... He was so much more fun to watch when he got a whole tank to himself! Plus, as a college student you really can't afford to be cleaning his water every three days and buying all the medication he needs when he contracts illnesses from being in bad conditions.