First layer test result

I am looking at a large print ahead; many parts need to fit together. Not sure if my bed is concave or not, but don’t want to jump into this print and end up with prints which don’t fit. New to 3d printing. Can someone give me a review of my first layer print? Pic attached

EDIT: printing using Polyterra PLA Pro (using stock Polyterra profiles) , 0.4mm nozzle, standard 0.2mm profile in Bambu Slicer with everything stock.

A single layer is not going to tell you if your bed is warped.

Parts fitting together how? Small parts, full 200mm long or square parts? More info needed.

If they are small parts, I would be more worried about dimensional accuracy then a flat bed (which the pre print bed leveling adjusts for).

If it is a large print then you need to print a test bar 225mm long by 20mm wide and 20mm tall and if it stays attached during print, you can check for flatness when it cools and comes off the plate upon completion.