I have Avira Antivirus, threatfire, spyware-blaster, and ad-aware protecting my pc? Am I safe?

I used to have just avast, spyware-blaster, and ad-aware. I was unhappy with avast and switched to avira because of it's better protection rate. I am aware avira does not have a firewall. Should I download an additional firewall alongside windows firewall? Is this configuration safe?