When I was 7 weeks with my first, my doc (private, whom I trust completely) only advised folic acid. It was too early to take Materna and he advised me to stop all my multivits because of unnecessary iron content. I took Materna only later on. So my guess is you don't need more.
If not for issues early in my first trimester, I wouldn't have bothered to see a doc before my 2nd trimester. Now tht I am with my second, I didn't see a doc before my 3rd month. It could just be me, but personally my view is, if you aren't bleeding, you are fine.
By the way, at Tsan Yuk, they don't do scans. I saw private and public at the same time and at private clinics you do scans during every visit/month which I thought was a bit excessive (unless you are high risk etc). At Tsan Yuk, they achieve the same result by feeling your tummy and using good old measuring tape!
Hope this helps. Don't worry too much!