Cheek hurt in wisdom tooth extract area.

I have removed my upper right wisdom tooth in July. No stiches done and it was healing good. I see some hard bump on the gum in August and went back to OS. He told me to wait for 2 weeks and see if it goes in its own. I waited till this week and went back and that bump was giving me pain. I went neck and he said he want to shave that down. He put anesthesia and kind of scraped it for a while. Don't know exactly what he did. Did something like scraping and did stiches. He said stitch dissolve on it's own. Never had dental stitches before and don't know how to identify if it dissolves. From yesterday, I have pain in the cheek( the area inside the mouth which is top of the wisdom tooth extraction and inside the cheek where cheek meets the extraction site). Those area inside is very sore. I see in the mirror and it looks red and looks like some scratching. Don't know if dental work scratched the cheek area and top of the gum area too. Is it normal to have these type of scratching?