Freebies.....
If it's the one I think it is, unscrew the plastic part which goes onto the valve and there should be a rubber piece inside (you may have to knock it out). Turn that rubber piece the other way round and screw the plastic bit back on. I ditched my pump which was similar as it wasn't nearly as good as the reviews suggested it should have been.
Freebies!! How! Where!

I did that but it won't lock on to the valve and I can't see the pressure indicator working either.
I'll take it back to Halfords with my front wheel tomorrow.

Just want to double check that before trying to inflate you unscrewed the locking nut on the presta valve and gave it a little press to make sure it's not stuck.

I've been out and done 33 miles. I could have stayed longer and done more, but I'd lost my nerve on some of the twisty downhills and had to walk down one bit and was mocked so I peeled off early and went home rather than doing another set of twisty bits
I really need to learn to descend faster, brake better, corner better... I just don't trust the brakes on the bike to stop me in any sort of sensible distance and I don't trust the bike or myself to corner well enough to not just slide into a wall or a parked car or off a cliff. Any suggestions, or is it just a case of practise, practise, practise until I'm more confident?

Yeah did that and that's why both tyres are now flat.

Old fool.
I strolled into Halfords with pump & tyre and said 'I'm either thick or it doesn't work'.
As soon as I handed the pump over the assistant immediately said I'd put the internals the wrong way round and it now works.
Now I've blown my tyres up I've realised that the pump is OK for emergency but I probably need something in the garage to do a weekly check and pump up.
I was looking at the Topeak Joe Blow or for my purposes would something like this do? - http://www.halfords.com/webapp/wcs/...uctId_700388_langId_-1_categoryId_165661#tab1
I've been out and done 33 miles. I could have stayed longer and done more, but I'd lost my nerve on some of the twisty downhills and had to walk down one bit and was mocked so I peeled off early and went home rather than doing another set of twisty bits
I really need to learn to descend faster, brake better, corner better... I just don't trust the brakes on the bike to stop me in any sort of sensible distance and I don't trust the bike or myself to corner well enough to not just slide into a wall or a parked car or off a cliff. Any suggestions, or is it just a case of practise, practise, practise until I'm more confident?
Where are the hills you are struggling with, so I can have some idea of what you are up against/judge you
When its dry here I don't touch the brakes on the descents ever, just need to switch off and go! I take it easy in the wet/damp as the roads go very greasy here and I use slick tyres.
You need to trust the bike - it will grip in the dry! Just feather off speed with the brakes until you're happy and go a little faster each time.
To get off and walk down - just how steep are we talking here?
Here's the Strava ride. I don't think it helped that most of these are blind turns, so I didn't want to cut the corner and end up on the front of a Range Rover. It is also a bit damp around there because there's lots of run off from the surrounding hills. That's all excuses, though - the real problem is me cornering like a big girl. I really don't think I trust the bike to not just slide out from under me, and when I'm going down some of those slopes I can have the brakes on full and they don't do a damn thing to stop me. I find it helps to pump the brakes a bit, like ABS on a car or something, but I don't know if that's the right thing to do or what. Maybe the brakes are rubbish, or maybe I just need to get used to brakes on bikes not being up to much full stop!