Questions about Prenatal Blood tests?

Ok so I am currently 11 weeks pregnant with baby number 2. My first child is 9 1/2, so it has been a while since I have done all of this prenatal stuff, and times have changed since 10 years ago. I had my first prenatal blood test, and pap smear a few weeks ago. Everything was good for the most part. My thyroid level was low, which I was told could be due to hormone changes due to pregnancy in the first trimester, and it should level back out in the second trimester. Does anyone have any experience with this matter? Also I had a full std panel and hpv, excluding hiv checked. I came back with a minor yeast infection which caused my pap to be abnormal. I have never had a yeast infection before, but was also told it could be due to the hormone changes, and is common during pregnancy? Again thoughts from anyone with this experience? Also back to the stds, like I said I was checked for it all but hiv. The only reason I wasnt tested for that was because I have had the test done before, during my last pregnancy. I have been with my husband for over 3 years, and felt that if I had something like that it would have shown up somewhere in my blood work. I have also never had an STD, so it would be unlikely to have hiv right? But then I got to thinking I should just have it done for peace of mind, because its bothering me LOL! So I think I will have it done on my next blood work. Thoughts on that as well? I would appreciate answers from ladies who have been there and know what they are talking about. Thank you.