Before bringing me to mammogram, they asked for history like at doctors office. Then no doctor saw me. Is this the standard process?

Yes. The history is important for the radiologist, when reading the mammo. Generally, in a screening setting particularly, the radiologist does not see the patient, much like the situation with most other xray studies.
It is common. The history is important but routine screening mammography does not require a radiologist to see the patient to complete the examination. If the patient has a physical sign or symptom, then it is no longer a screening mammogram but is then referred to as a diagnostic mammogram. That may or may not require the doctor to see the patient to complete the test.
Yes. It is a radiology test like an x-ray. The history was mainly for the radiologist when he reads your mammogram but also for the techs in case there's something to be aware of for the test.