First things first, go to Mojang and secure your account. So you know you're in good standing and that you know with a fact what your login details are. Login then with your email and the set pass. If it fails then, it could be a couple of things, server side and client side.
Server side, auth servers could be temporary down. Check the mojang status page.
Client side, you're using some security or anti virus software that blocks internet connections and you need to whitelist the app. You mention you're not, so perhaps in your router the outgoing traffic is blocked somehow? Are you on a proxy, tunneling ipv6 traffic, or a vpn, or anything like that perhaps?
Is it just Mc's launcher, or also steam, and other platforms?
What if you temporary connect to some neighbour's open wifi?
What if you use another system on the same or another network?