Any dental workers in here?

Help? Opinions?

I got the below tooth filled last week (yes my husband took a picture of it when the dentist gave me a quick break lol) it’s given me major pain in the past but hasn’t really been bothering me lately. I needed other dental work done that day so I just decided to take care of them both same day. It was a deep cavity and the doctor said I was SOOOOO close to a root canal , thank God i didnt need one! 😌 Now that it’s all said and done, it’s been good for the most part but every so often I’ll get that feeling of like a ‘brain freeze’ but in the tooth. I just had some ice cream and it shocked me in that tooth for a minute. What could this mean? I don’t think that this is normal to feel?