We found this spider in the corner of our conservatory last night, the picture of it has been zoomed in (it's roughly around the size of a 5p coin) I can't tell whether it Is a false widow spider or not but there's more of these same spiders in the corner of our conservatory.
Yes this is a false widow (Steatoda nobilis). It is possible that you have more, especially in a relatively large area like a conservatory, but do check that the others are not simply more common, harmless species such as missing sector orb weavers (Zygiella species). False widows & missing sectors can overlap territories, the false widows aren't seemingly bothered by the smaller spiders, but may chase off bigger competition.
Yours appears to not yet be fully mature, still stripey around the legs. She may live another year, maybe 2? When they set up a web, with a good hiding place nearby, they are often loathe to move and generally stick to their web. They do love conservatories, as well as porches & window frames/under sills.