why is this happening
See this through and you will find out.
I thought by having avast I wouldnt have any major issues
Then you were mistaken, no offense intended. All the AV companies play catch-up. Almost everything they do is a reaction to what the people who write malware do. Much like how the police can try
to clean up the streets, but they have to wait till a crime is committed to take action. That not to say they cant stop most bad stuff that is out there, you still need a AV on any Windows pc, but sooner or later they are going to miss something for an unfortunate minority of users.
The first rule of possible infection is do not panic
, and no offense, but you seem a little panic stricken. So 1st, relax. Then read Tech's instructions, the 5th one in particular. Avast! is still protecting you, the Network Shield alerts are most likely caused by an existing infection trying to download more infections or send out your personal data, and Avast! is stopping that. You definitely do not need to go buy a new laptop, no matter what is wrong. With a little of your patience and time, we have people here who will get you cleaned up and running again soon.