It's either that you blacked out or that you got bad phenazepam. If you got the phenazepam recently, it is more likely to be bad as there is a ton of poor stuff.
The LD-50 of benzos are pretty high, but 1g of phenazepam would be pushing it. Even if it was cut to 10% purity, that's still 100mg over a week or 14mg per day, which is a ton. Considering the long half-life of phenazepam, even half of that would strongly effect you for longer than a week. I'd say it is most likely not phenazepam, or a very, very small amount of it.