Estimated Tax Payment Calculator I Missed My First Quarterly Estimated Tax Payment, Should I Combine It With My Second Quarterly Payment?

I missed my first quarterly estimated tax payment, should i combine it with my second quarterly payment? - estimated tax payment calculator

Or am I to them separately? And I have to pay the federal tax calculator and ask me only about 15-18% of my estimate of gross income. I expected that about 30% or less. My level of taxation is lower.