have a headache or having a headache

[s.clke]

I have had a headache for several days.

I have been having a headache for several days.

Which is correct? if boths are correct, what is the difference?

[Rover_KE]

I have had a headache for several days. The headache has been constant for several days.

I have been having headaches for several days. They have been coming and going.

Rover

[s.clke]

Thank you for your answer.

>I have been having headaches for several days.

I see.

>I have been having a headache for several days. ---- so this doesn't make sence to English people...

[Karima-19]

Thank you for your answer.

>I have been having headaches for several days.

I see.

>I have been having a headache for several days. ---- so this doesn't make sence to English people...

Yeah, this is English! You have to give more attention when you want to transfer what you want to say!.

[Karima-19]

Rover

You make it more meaningful, thanks.

[Verona_82]

I was taught we shouldn't use the expression 'have a headache' in a continuous form, for instance 'I'm having a headache'
However, it seems to work with the present perfect continous. Could you please explain why it is so?
Thank you.

[Tdol]

>I have been having a headache for several days. ---- so this doesn't make sence to English people...

It's sounds odd; if it's a single headache, then the present perfect simple sounds more natural to me. A headache's a state not an action, and we don't use progressive forms in exactly the same way. My head's been killing me/aching/hurting for several days would work IMO.