Go for it ! 
You can buy a simple keyboard set , an old used one for very little money and just plug into your computer and play on a software. Creating music on computers is amazing. Since you virtually have no limits. It takes the physical aspects, hands, coordination and other elements out of the equation and allows your mind to roam free. It’s really amazing and it will open you to new things which will improve your skills on any instrument.
If you’re using a PC , Fruity Loops is a very nice and very easy to use software that allows you to create loops. (leading to tracks…)
You can also check out Reason (created by Propellerheads).
If you have a mac, as I do, GarageBand comes built in with it. And if you wanna go more advanced, You can either get Apple’s Logic (which I don’t have any experience with so I can’t recommend, but I do have a positive feeling when it comes to Apple’s products.) or you can get Cubase, which is what I usually use. However, the new versions of everything will cost you quite a bit of money. You can probably download older versions from torrents …
In any case, you can channel your creativity towards everything, anytime…
If you’re just walking down the street, imagine for example (Ld4all…) that you’re in a lucid dream and what you would want to do . Think about what you would do right now if you could teleport , do, be anything you want to. Think about drawing things in the sky, building creative structures/rooms etc… Think about cool items/shirts/other clothes you’d like to wear. Invent acrobatic drills that no one has ever done. Be creative about ways to be creative… !! You don’t have to do something physically to express yourself.
Creativity is inside. You can do all those things in your mind and you’ll feel like you’re expressing yourself. You don’t actually have to build buildings, or write on the sky. You can, and if you want to, you should, but express yourself regardless of what you physically do.
There are probably lots of activities which you habitually engage in. Use that too.
If you’re an advertiser , for example, then you can think of incredibly creative advertisements , whether they make sense or not. It doesn’t need to make sense. If you’re a doctor, you can think of diseases that people might had in the distant past. Or maybe about miracle remedies.
Also, try changing the things you’re most afraid of changing in your life. Those are the things that will free you the most. When you make a decision to change something that you never even considered changing, your mind starts getting the idea that maybe change is good for you. Because, the more afraid you are of change, the harder it will, it makes no difference if the change is positive for you…
Most importantly
^^ Have Fun ^^