ive been on 20mg for abit now i took one pill in the morning and felt awful tired and out of it plus i couldn't sleep. I changed it to having it after i got home from work after my tea and i now have no side effects at all.
Yes, 10mg could have been enough. And might not have. We all metabolize drugs differently. No way to know if you go up to 20, but that is a more therapeutic dose for anxiety. See how the side effects go, if they stick around for a couple of weeks ask to try the 10mg again and see what happens. Some people just metabolize things much more strongly than others.
It's very typical (common even) to experience some short lived side effects (like the ones you describe) after increasing your dose of Citalopram. The side effects should start to improve after about a week, maybe a little bit longer. I would recommend just giving it some time, and of course, keep your doctor abreast of the way you feel.
Also, just like when you first start an antidepressant, these meds take time to make noticeable differences in anxiety. It's normal to expect to wait 4-6 (even as much as 8+) weeks to be able to fairly assess the effectiveness of the medication. Same thing applies with dosage increases, although typically the adjustment period isn't quite as long. Therefore, give each new dose ample time (a few weeks minimum) before deciding to make any changes with the dosing.
Hang in there, let us know how you're feeling!