IMHO it's probably not cause for concern yet--last package I orderd from alexer1 took that long. With Russia's indiscriminate attacks on civilian infrastructure, it'll happen. Also, one UA seller (Nevidomuj, I think) sent stuff in bulk to a Minnesota address, where it shipped from.
USPS has lost and/or returned a few international packages for me lately. Now watch the progress with Informed Delivery, and I file a missing mail report if making a wrong turn (like, back to a farther-away sorting center).