My car brake pedal has been feeling "hard" when I press it since
Thursday, I would appreciate any advice on what is going on and if it
is safe to drive like that as it is a new week so I have to decide if
I should take it to a garage or get my breakdown service to check it.

I had this problem before a couple of months ago... the brake pedal
felt hard and I took it to my local garage and they said there was an
air leak effecting pressure (or something) and they fixed it- I then
picked it up and it was fine and then went hard again and even worse
my car then started stalling! so I took it back and there was another
air leak and they changed it and told me it was safe to drive.

However, the pedal felt firmer than it ever was before (although not
hard like when I took it into the garage).

So not happy I called out the breakdown service and they checked it
and the guy said that although the pedal was firm it was perfectly
normal and nothing to worry about - he took the car for a drive and
disconnected the vacuum pump (I dont remmeber if that is what it was?)
from the brakes to show me the difference. In the end he said that it
was fine and the brakes feel different because from when I got the car
there was an air leak making the brake pedal softer than it should be.

I have been driving around without any problems like that and even
became so used to the firmer pedal that I stopped noticing it! and
then on Thursday when braking the the pedal suddenly felt hard again!

I am having no other issues, no stalling, just a hard pedal! I have
been driving around since then quite a bit and although the pedal is
hard I have no problems with my brakes other than the fact the pedal
feels wierd to me as its hard again.

I am no expert (not by any margin) but I find myself unconcerned about
my brakes as it simply feels to me like there is a loss of some
pressure from the vacuum, like when the RAC (breakdown) guy
disconnected the brakes to show me. Maybe that is something I should
be concerned about? I don't know that is why I am posting here!

I would appreciate any advice on what to do now? is it safe for me to
drive the car like that? should I get it checked out on Monday (today
for me as I am in England).