The Cdc says fifty days is the average time for antibody detection. Your 6.5 weeks is 45 days so you are close. Imo, you have rounded second and are heading into third. Snorting drugs is not as dangerous for Hcv transmission as injection but a risk none the less. If you have a drug problem, get into rehab. If this was a one time incident, learn from it and remember the anxiety and worry the next time you are tempted.
If I were you, i would have one more antibody test at 3 months and then get on with your life, drug free.
If you had a PCR test then yes the virus will be detectable by then.
If you only had the AntiBody test then it can take up to 6 months with most (90%) having them by 12 weeks.
The association between sharing coke staws and catching HCV is a little week.
CS
I feel it probably is a good enough time.
But---- on that note, I would suggest (just to ease your mind) another in 6 months --- and then annually.
I'm pro testing.
Meki