Immediately after a fantasy draft concludes, half the room is thinking "I own this league. Carve my name into the trophy today," while the other half is thinking, "How do I trade this entire team right now?"
Obviously, it's too early to know what your team will do. But there are still some bad signs at this early stage in the season. None of these things mean to go crazy and rework your entire roster, but they are things to keep an eye on as the month progresses.
I generally avoid trading for the first three weeks of the season just because no owner is rational. Everyone is panicky and with most deals that early, the owner lives to regret them.