No more trading for two weeks, barring a landslide in your favor. Just stop! You don’t know anything about your team right now. Just wait and see. In two weeks, you will have some basic idea about your team and its needs.
Also, don’t go out and join any last second drafts. Those leagues fall apart very quickly. I recommend no more than three teams per season. If you have any more than that, you will either end up obsessed, and wasting time on fantasy that needs to be spent on real life (friends, family, work…) or you will end up not being an active participant in any of them.
Neither is good.
18 hours before first pitch, you are where you are. Set your lineups and take a deep breath.