MBP just started giving me 3 beeps for RAM months after upgrade

I upgraded my MBP’s RAM to two 4gb sticks from crucial and a Samsung SSD, after heavy use earlier in its life. It’s been working fine for about two straight months, and today when I took it out of my backpack and opened it, it gave me the three beeps. I restarted it and it seemed to work fine, but then froze and shut down twice after that point.

I currently don’t have the right tools on me (I’m away at school) so I can’t check the actual RAM slots. Is it likely that somehow the ram got jostled enough to not be in the slot anymore, or something like that? I’d hate it if one or both of the sticks went bad so shortly after buying, which certainly doesn’t seem to be the norm.

Any other software tricks for this issue, or should I just order the screwdrivers and check?

Thanks much.