I was in contact with someone that tested positive for covid. my last contact was the 16th the 18th he started to feel bad, informed me and i isolated from the rest of my family today is the 25th and none of us have symptoms. should i stay isolated?

Minimal outside time: To avoid spread of COVID-19, use precautions such as staying home as much as possible Avoid contact with others until the infection rate begins to decline. Monitor your temperature, rest and drink fluids. On day 7 post contact if you have no symptoms, most likely you are fine. Continue to use good hand washing and keep surfaces clean.

Yes: Currently, most guidelines say to stay isolated for 14 days from last close contact with a person with COVID-19. Check your state's guidelines. Also other steps you should take are listed. Here's the one for New Hampshire: https://www.dhhs.nh.gov/dphs/cdcs/documents/self-quarantine-covid.pdf