Sorry, you may not ask questions on someone else's thread and I deleted your attempts to do so. If you need a personal reply, you'll have to pay the fee and post a new question. But I suggest you save your money; the answer to your question is easily availale just by reading a few threads.
Welcome to the STD forum.
Question 1)
First, you have the common misconception about sexual transmission of hepatitis C virus (HCV). It is not an STD; the only situation in which sexual transmission has been shown to be a signficant risk is among gay men with particularly traumatic rectal sexual practices, with bleeding. Also, HCV is not known to be transmitted by oral contact with blood. I can't tell you there is no risk from the exposure you describe, but certainly it was very low.
As for HIV, that's also zero risk for practical purposes. If your partner had HIV, she would have told you. (Why would she tell you of HCV and not also tell you of HIV? And you can be 100% sure that if she is known to have HCV, her doctors have tested her for HIV.) And even if she had HIV, the chance of transmission by oral contact with menstrual blood probably is very low. HIV is not easily acquired by oral contact of any kind.
2) 4 weeks was too soon. Have another HIV test at 6-8 weeks. I'm not sure about HCV test timing but I believe 6-8 weeks also is fine.
3) You read wrong. The blood test is accurate for judging HCV infection, with or without symptoms. If your blood test is negative, you don't need to worry about it any futher.
Regards-- HHH, MD