Garda stops car of lone woman at night

If a woman is driving home alone at night, and is stopped by a Garda car, what are the rules?

I was stopped recently, I had just phoned my husband to let him know I was leaving for home (5 minute drive). As soon as I saw the flashing blue light, I pulled in immediately, as I thought he might want to overtake, but he stopped behind me, and got out. He just checked the tax, insurance and NCT, and asked why I was out late (just after midnight, midweek). I told him I had just been talking to my husband, and I would ring him again now because he is expecting me home in minutes, so he just asked me if I had been drinking, I said I don't drink, so he left me drive on.

Just curious to know if you have to stop in all circumstances. This was a quiet rural spot, and I felt quite vulnerable, so I kept the car door locked, and only opened the window a little.

Any one could have a blue light flashing on their car, he didn't have any ID either, and a plain looking uniform. Could I have driven on, and let him check my details at home?