2.5 weeks ago had kidney pain/passed stone(?) for 5 full days. hx of 4 passed stones only lasting 1 day & no utis.urine was entirely bright red/had grainy streaks of blood. period is 10-12 days late & neg. pregnancy test today (39 days). am i ok?

Your cycle has probably just been disrupted by the stress in passing the stone, but you need to continue to be careful since you cannot easily judge where you currently are in your cycle. Hopefully you are done with the stones now and everything will have a chance to heal.

Yes you should be. Drink plenty of water and make sure you are under care of a Urologist for yor stone problem.