If I understand correctly you have two anti-virus programs running - Norton and F-Secure. This will definitely slow your system down. You need to choose one and uninstall the other. Personally I would ditch Norton as it is a resource hog.
OnePlus 5 review
Alice Saey's mesmerising animation for Dutch singer Mark Lotterman
iPad Pro 10.5in (2017) review
Comment booster votre iPhone ?