Hello!
I agree that this does look like a seed from the Fabaceae. Since the seeds appear to be immature and deformed, identifying them may be challenging. Clues that would help are the colour, size and hilum.
The seed looks to be a solid colour, no patterns or markings. They also seem small (largest at 5 mm?); one would have to estimate the size when mature and filled out.
The hilum is facing L on the seed in the tweezers, and R on the middle seed. The shape and size should be similar to the mature seed, and direct comparison with known seeds should help. It looks to be longer than wide, so is likely not a Fabaceae species with a round hilum such as Trifolium spp. (clovers).
I would suggest checking Pisum sativum (pea) or a species of Vicia (vetches) before looking into weedy species.
Please let us know what you found!
Thank you, Jennifer