Think my flash drive is infected by a virus

I don’t know whether my SanDisk cruzer 32Gb flash drive is affected by a virus. Whenever I plug in the flash drive on my laptop, I am experiencing hangs when I am using the internet. I am using the free antivirus Avast. I didn’t feel any significant interruptions when not connected to internet.

My system and internet details are below.

PC  Lenovo ThinkPad

ISP DSL Acanac

Could my flash drive contain a virus? I have not saved anything back from the drive to the system. Or could it be the problem with my system? Also, please suggest me an antivirus that can be used to secure the flash drive.

Thanks in advance.