As per your description it might be an infection but the only thing is that u don't have pain.If it's a sudden swelling and increasing with time then please consult your dentist as soon as possible.

Your symptoms are suggestive of a local infection which could likely be a tooth infection. I would advise you to visit the dentist so that you can be examined and be treated as per the underlying cause. These following steps may help: - Apply ice over the area that is swelling. - Do salt water gargle with lukewarm water thrice a day. - Brush your teeth regularly, preferably twice a day. - If you have habits of chewing betel leaves, tobacco, etc kindly stop If the condition persists or worsens visit the dentist at the earliest

Swelling can be because of any reason.. Tooth related too. get yourself checked by a dentist asap.