Single entry X but need to visit HK

I am on a student visa in China right now, but I have only one entry so if I want to leave and come back I would have to apply for a second entry. However, my parents are coming in two weeks on a tourist L and we are going to Hong Kong 3 days before our departure back home. Is it okay if I have a student X and fly from Beijing to Hong Kong, then from Hong Kong to Shanghai the day before my flight back home (Mexico) ?