Wow, yeah that picture makes my head hurt a bit....
sorry have to edit, one moment
Ok, so the left side of block right side wires appears to be phone pass through. The far left cable should run outside to your phone block. the remaining four cables will be (generally speaking) the phone jacks throughout your house.
The right side of that block indicates that you have two internet ports wired up in the house.
Generally speaking a phone jack will be on RJ11 and have a small square plug for a phone. Internet port will be RJ45 and is bigger, rectagular.
In theory you could remove the plate from the wall in your bedroom if you don't straight away see an RJ45 type plug there. You would be checking to see if all 4 pair (8 wires) exist in that box. Each pair of those wires can be utilized for a phone line, and they easily could have tapped into this cable in another room to put jacks there off any number of those pair before or after your room.
With that said...as suggested above you would use a tone generator to find out which of those cables running down to your structured cabling is the one to your bedroom. If it wasn't spliced then you can convert it over to one of the internet ports simply by punching it down to the appropriate port, changing the plate/jack in your room, and a couple of CAT 5 cables. Keep in mind that if the phone service is active the tone generator may not work on the primary pair. In theory you can walk out to your phone block and use the test jack feature to unplug the incoming lines there to allow tone to work. Since phones work in parallel you will likely get tone on all the wires connected on that block unless you take the time to pull each off the connectors....in that case you would need a punch down tool to reconnect them since this isn't an 86 block and there are no bridging clips.
In truth, a professional in this field could make short work of determining what is and isn't possible with a quick look in person.