1st time traveller

As the title says, will be my very 1st overseas adventure. I'm 40. From Australia and planning on 7 full days in Phuket. I know absolutely nothing. Some things I would like to know to get me started. I'm a non drinker but I use Marijuana medically as well as socially. My questions revolve a little around this. Minus flights and accommodation, would $1500AUS be enough for a decent week there? No drinking, lots of smoking and street food, some light shopping and I'm looking into a small traditional sak yant tattoo from a master. Also possibly an elephant sanctuary, tigers and some temples and buddhist stuff. So those will be my main costs,and activities I would like to cross off my list. Are all these things achievable with my budget? And do I need to bring any medical marijuana scripts or proof I'm a patient or is it all pretty relaxed with buying legal over there? I won't be travelling for another 12 months, so things may change in that aspect by then, but any current info regarding that would be great.