I noticed a tiny hole on my septum the size of a pen nib. Does a hole that size repair itself? Are there treatments to seal it?

Hello, thank you for your question and provided information. Based on them your issue can be adressesd septal perforation that you desribed as a tiny hole and unfortunately they do not heal itself.
You are 2 months post-op which mean you are in recent healing phase and an intervention should not be performed. After completing your healing process with a well-executed revision operation, your issue can be fixed. During healing process you need to follow up your surgeon and given instructions.
Best Regards,

From your description, "the size of a dot mark made by a thin pen", you may have a micro-nasal septal perforation. I am sorry this happened to you. Unfortunately, even these tiny pin hole perforations will typically not heal themselves. If you keep this area clean, free from scabs infection, the opening should "stabilize and heal" permitting your surgeon to consider repair at a later time. Tiny holes are generally easier to correct, but you should have a discussion with your surgeon about recommendations for correction. Patients who report whistling, bleeding or crusting are the best candidates for repair. If this micro-nasal septal perforation is completely asymptomatic, however, you may wish to do nothing. Hope this helps. 

Septal perforation can occur after septoplasty or rhinoplasty. I recommend that you visit with a board certified facial plastic surgeon who has experience in repairing septal perforations. Your options include doing nothing, having a septal button placed, or having surgery to repair the hole. If the hole is not addressed it may get bigger, begin to whistle, bleed, and cause obstruction of your nose. I wish you the best, Dr. Ardesh