Pregnancy and headaches?

Since last night I have had a headache on my right side of my head only. I took some Sudafed last night before bed because I thought it was a sinus headache but the pain never went away.

Normally I would take Motrin for a headache but since it contains Ibephrophen I can no longer taken it now that I am pregnant.

I had the headache all though the night and still have it this morning. I awoke every hour or so to change positions last night and to pee as a result of the pounding head.

Strangely enough when I am in the tub and putting all mt weight on the ball of my right foot to support myself as I lay flat the pain goes away. That is the only thing that has relieved the pain for me. I can't me in the bath all the time though.

I am miserable here and just want the headache to go away, does anyone have a suggestion on what I can to to alleviate the headache? What is causing it and how can I fix it?