AirAsia gets you around Thailand cheap and quick. February is high season and it is better if you book some accommodation immediately as the best and cheapest places are gone already. Air conditioning is good as it gets quite hot there. AirAsia also goes to Hong Kong, Singapore, etc if you fancy some days elsewhere.
A helpful site for Bangkok:
http://bangkok.sawadee.com/
Asiarooms is good for accommodation in Thailand. If you look, you'll quickly find company there, though it may turn out not to your liking. Otherwise, as said, it is safe for people on their own in Thailand.
Beware. February 14th is Chinese new Year. In some places, few shops will be closed. In others (like Singapore), most will be closed, for days. Also be careful of pick pockets. Lots about, especially in Bangkok. Do not accept a drink from a stranger, or leave one on a table for a few minutes.