if you chilli is still outside in a pot, bring it in now or the colder nights will kill it off. Place it on a warm windowsill and keep the compost barely moist. The wrinkly ones have probably become overripe and should be picked and used. Normally the slimmer or smaller the fruits, the hotter the chilli. When all the fruit have ripened and turned red, prune the plant back by 50% and with luck it should eventually start growing again. Nest spring, if it's still alive, repot it with fresh compost, teasing as much as possible of the old compost off the roots and give it a liquid manure feed.