[Closed] And now my boiler has packed up! Honestly, how many more things........

Try bleeding again once the radiators are cool again to just double check all the air is out the system.

If the house is very cold and you need some heat, you could try running the heating on a lower setting and/or bleeding some more water out the system. Possibly those things are enough to keep the heating going without the pressure going into the red.

I've just moved house. When the heating was running the pressure went up to 3.5 bar 😲

I bled the rads (without the pump running, as above, otherwise you can be sucking air in rather than out). Got next to no air coming out, but maybe a pint of water cumulatively. The pressure's bob on now.