It is definitely possible that this black dot on the inside of your cheek is from accidentally biting your cheek or otherwise having trauma to the lining of the cheek. This is especially the case if the area is also a bit tender, suggestive of a recent injury
Most likely, the reason that the area is black is because with the injury, small blood vessels were broken, allowing some blood to leak out into the tissue. This small collection of blood would form a 'blood blister' under the lining of the cheek, which would appear to you as a small black dot. If you are having significant pain, swelling, or if the black dot is enlarging, you definitely need to show it to your primary care doctor
. They can confirm that this is a blood blister from a minor injury to the cheek, and they can also rule out infection or any other complications requiring intervention.
Also, if you did not bite your cheek and there is no evidence of injury, then you also need to see your primary care doctor, as a black dot in the mouth without injury might be a sign of an early melanoma, a type of skin cancer.