If i had a negative herpes blood test at three weeks and seven weeks is it possible i still could have hsv-1?

Sure: If you just caught it after the last blood test, you would have herpes-1 now, but a negative last blood test. Herpes-1 is commonly found in people by the time they become adults. It is common enough that it is considered normal to have herpes-1 oral herpes. Usually, there is not a reason to repeated tests for herpes-1 unless a person is worried about catching it on his genitals via oral sex.