No sleep in the Evans House

Oh dear. For some reason the last few nights Tully has gone to sleep absolutely fine when we've put her to bed, but she's then woken up and is wide awake at about 3-4 in the morning and nothing we do seems to make her sleepy again for a couple of hours. Mark and I are both absolutely knackered! I think her gums are hurting her, as she's generally more restless too the rest of the night. Any advice gratefully received - we're both getting rather broken. She's gone off the Dentinox stuff I've been using - she used to love it but now it seems to make her cry more. Last night we resorted to Infant Nurofen, but not sure that's good for a longer term solution :(