I don't think you should be scared unless you have preexisting health problems that could be exacerbated by air pollution. 5 weeks is nothing. Where will you be going?
Tianjin, Beijing and Xi'an...the most polluted cities in that video lol.
I had allergies and asthma as a young child but I haven't had lung problems like that in over a decade. Do the masks actually help? I might just bring some and wear them, if so.