You can get a radiographh done or intra oral examination to precisely evaluate the extent of decay. From the picture, it seems to be incipient caries. A tooth colored filling should suffice.

Ma'am, You need to visit a Dentist. Let them check if the defect visible requires a filling. A photo would not give the correct picture. A composite filling would be preferable if required.

It is small cavity can be easily filled.you can have better restoration filling than silver as gic or composite.But dont delay ,it can deepen .

Yes, caries started in your tooth. It's better to get it filled. Their are better options then amalgam or silver filling. These days silver fillings are not advisable as they can cause silver toxicity. You can go for GIC fillings as they are safe and esthetically good . Still have queries then you can consult me online or offline for better guidance and treatment options.

Hello dear Please be aware See it is an incipient caries so you prefer gic as compared to amalgam or silver filling.donot have a deeper cavity.for further details you can consult me Thanks