infections and viruses

Hi i recently got a 360anti virus on my laptop.Thanks to your site i managed to remove it using the Malware download.Previous to that i downloaded pc docter and was horrified to find i had hundreds of low risk infections along with some med risk ones.Malware says my laptop is infection free yet pc docter tells me i still have lots of infections.I hace to pay to continue with them to remove the infections.Are there any free tools apart from malware that will remove them all.I am currently using Avast as my anti virus .