[Grammar] I have taken some medicine, but it (did not help/ has not helped/is not helping)

[naweewra]

Hello,

Which tense sounds the most natural?

I have been having a headache all morning. I have taken some medicine, but

a) it didn't help
b) it hasn't helped
c) it is not helping

(= I still have a headache)

Thank you.

Nawee

 

[5jj]

I have had a headache all morning.

I took some medicine, but it didn't help/hasn't helped.
I have taken some medicine, but it hasn't helped/isn't helping.

These are all natural.