I had a root canal on one tooth two days ago, all was fine initially, but on the second day had quite bad toothache, so took Paracetamol to relieve it. Then started to get a slight blistering mouth just above tooth. Now in the second day, my face is swollen on that side, and still painful, but maybe little less than yesterday. Im mainly concerned about getting an infection in the tooth and root.
Thanks for your query.  I have gone through your query. As far as the pin and swelling following the root canal treatment is concerned it can be because of the endodontic flare-up or remnant previous infection. Nothing to be panic, you can take a course of antibiotics like amoxicillin and metronidazole combination (if you are not allergic). Do saline gargling. You will be fine withing 3 days. I hope I have answered your query Take care.