help, my bag disapeared!

Hi everyone!

so, i was wandering around in search for some skill books that i desperately needed. i found the book store, and in it there was also a backpack. i loaded my dufflebag full with the skill books and searched further for other stuff i could need. put my dufflebag on secondary while equiping the backpack for more storage. them i went back to my car and wanted to throw the dufflebag into my trunk, but it loaded forever. suddenly my dufflebag was gone, its not in the trunk not on the ground and not in my inventory as i said, i really needed those skill books. is there some way that i can retrieve my dufflebag with its loot? i am playing vanilla currently btw, since i wanted to get a raw experience again.

Thanks for the help!