Congratulations !
Insurance on a car often takes into account security features on a car too, so on a little for Ka, the locks will not be as secure as say a Honda that would have more gadgets built into the locks and ignition to stop someone stealing it.
Buying a brand new car as a first time may seem like a good idea, but what with the fact that for the first year you will no doubt (as careful as you are) be in a situation where you don't see a post when you park and open the door into it, or someone will scrape your car in a car park and drive off without a care.
Small engined cars are usually cheaper on insurance and you will also find that if the car is more than 10 years old, it will be lots more to insure than a newer one.
Another option is to buy a classic car and drive that on a limited milage policy for a year. It would normally have to be garaged or parked on a drive overnight, but for around £140 a year it works out a lot cheaper.
Remember that some classic cars can also be un-reliable though, unless you get an old Honda civic from 1990 and insure it as a "modern classic".
Oh the joys of motoring....It does get better as you gain experience though, think I'm on my 25th car now, only been driving since 1997 !