If your temperature is back to normal, and other symptoms have gone (leftover cough is OK), you can go back out after 7 days, even if others are still symptomatic.
Sort of. 14 days after the first symptoms in the household. (eg don't have to wait for a later starter to fully finish - if you've survived 14 days in a plague house, they reckon you are good to go!)
If your temperature is back to normal, and other symptoms have gone (leftover cough is OK), you can go back out after 7 days, even if others are still symptomatic.