Don't you mean "My head in pain happening is"?

You don't need to say 'पैर के', the word 'उंगली' covers any digit, and you can let context do the work for you. =D

yessssss someone who agrees with meeeee

in another question the correct solution to मेरे दिल में दर्द है was "there is pain in my heart". So why is it right in thet case but not this? Is it because of हो रहा?

उँगली is the singular oblique case. The plural oblique case would be उँगलियों .

The subject is दर्द masculine: In my toe pain is.