Hi Kimmy, welcome to OCF! Do yourself a huge favor and relax! Worrying will only be harmful to your health, it will not change anything. I know its easier said than done but please dont panic.

When a sore has been in a persons mouth for 2 or 3 weeks and not healed then its time to see an oral surgeon or an ENT (ear, nose and throat specialist). Make sure you make an appointment with someone familiar with oral cancer. Unfortunately most dentists do not run into oral cancer very often so cant look at something and tell you what it is. If the sore is still there in 2 weeks then it should be biopsied. Thats the only way to tell for sure if it is cancerous or not. Try to stay busy so the time passes easier for you.

Even by looking at photos, nobody here is qualified to diagnose your husband over the internet. We can only guide you in the right direction and offer advice.

During any given time a person who is otherwise healthy can develop mouth sores. It can be any number of different things. Most times it turns out to be nothing.

One thing you mentioned is that the sore did not hurt. That is one of the symptoms of oral cancer, a sore that doesnt hurt. I hope you dont panic over this but its just something to be aware of.

Since the holidays are coming up you might want to find a qualified ENT and schedule an appointment. It usually takes a couple of weeks to get in anyway. So this way you can always cancel it if the sore heals. Better to be prepared just in case. If (remember IF is a big word!) it would turn out to be cancer, it will have been caught very early and be highly treatable.

Here is more info that might help you.
Main OCF pages Diagnosis info