Normal
Given the fact that you surf and download files from unknown and shady websites, and the huge deal that you download malware samples for testing, you may be at risk.You shouldn't be switching antiviruses like you are (I have this one, then going to this one, when trial ends going back to other one). You should stick to one solid solution for your security and your system's stability.You should define ASAP a system recovery solution and a file backup solution. Your surfing habits tend to infect machines, therefore you should be prepared for the worst.
Given the fact that you surf and download files from unknown and shady websites, and the huge deal that you download malware samples for testing, you may be at risk.