Without a proper diet you wont get anywhere. creatine is a waste of money, save that money and spend it on food. Creatine wont make you gain weight, FOOD will. The difference from taking creatine vs. not taking it is next to nothing. All the hype surround creatine is a lie, I've been there, I'm sure when we all started we fell for the claims that you'll gain 10lbs-15lbs from doing one month of creatine. Then you have to go off for a month because of the "liver toxicity" and all the "damage" it's doing to your body. At 150lbs you'll benefit WAY more getting your diet together, and if you're not willing to do that, don't bother starting in the first place.
That's my rant for the day, I embarrassed myself asking these questions when i first started to. My advice, save the money and go buy more food. Eat eat eat, this is one of the best places to get the information you need. Use it.