Is my ford KA worth keeping?

Basically I bought my ford KA a few months ago back in March time.it's around 11 years old and it cost me just over £1400. Recently I bought new tyres and my friend did a relatively short health check on it as it's due for MOT at the end of July. He told me I'd need a new lower arm, and a new power steering grid thingy as mines cracked? He also said that I'd need my gearbox fixing as it's leaking and new whiper blades(which isn't all too expensive) I've already had my rear lights fixed and as I said previously I bought new tyres. As he's my friend he said he'd be able to give me a relatively good deal on fixing the rest however it still would cost me a fair amount but I thought I could handle it.

However, yesterday my bonnet started smoking and a warning light came on out of the blue everything was fine up until that point. After a few hours of me being distraught and crying I managed to get the car home. My friend looked at it and my heater matrix is destroyed? & apparently it's a large job and quite costly. I'm a student currently on a poorly payed job, having a gap year and hoping to work full time. I feel as though I'm spending money I don't have on a car that people keep telling me isn't worth it. But it's like my baby & it's so difficult to even comprehend getting rid of.

I just want some type of advice, being an 18 year old female who knows nothing about cars is really and truly difficult. I don't know what's best? Any advice would be much appreciated

A car, any car, is a money pit; the older they are the more you pour into them.

If you get rid of this car now you've lost about £1500 and you'll have to find a similar amount if you want to buy another. The next car you buy will have problems of it's own which you'll have to pay to fix.
Find out how much repairs are going to cost and work out if it will be cheaper than buying another car with it's own set of problems. Remember each problem you get fixed, so long as it is fixed and not bodged, is one problem less but there will always be another one just around the corner

Hi as any car sold for less than 2000 pounds never gets a warranty with it that should tell you something. So time in the case of this ford to think in terms of something a lot newer. The older a car gets the more expensive it gets.
don't what ever you do fall for the prestige car idea like BMW, mercees, audi or VOLVO they are huge money pits.
stick with the 5 and 6 years old fords and vauxhalls and even teh french models.

I haven't known my mechanic friend for that long, I recently got a new job and he's also a part time bartender at the same bar. Once he told me he was a mechanic he fitted my new tyres and did a short health check but he said the issue with the heater matrix isn't easily spotted so it went undetected.
Thank you for your answer, I'm very grateful to hear what people's opinions are!

You should have invited your friend to had a look at your car back in March BEFORE you purchased it and may be even paid him to do that.

Figure out how much total repair costs will be. If it is more than £1,000, scrap your car and buy a new one with the help of that friend