I have taken a needle onto a plane for darning in the ends of crochet and haven't ever had a problem about it.
This is from the EasyJet site You can bring tweezers into the cabin, and scissors with rounded ends and blades less than 6cm long. Razor blades are only allowed in the cabin if they're set in plastic. Knives with a blade not exceeding 6cm can be taken on board. Other sharp objects are not allowed in the cabin. For more information please visit our dangerous goods page.
I take scissors made for cutting babies' nails as they have rounded ends.