Weston Thomas - understand totally about your feeling of head exploding as i have got it all the time at moment.
Mine is not physical but purely anxiety and depression and the head gets so bad because it just goes round and round about what wrong with life at moment, so feels like exploding.
Physchologist been trying to help me stop this vicious circle and ruminating which is what they call it, but it is really hard to stop it.
So you may find that your head pressure is same as mine, and it is anxiety and depression making your head bad, rather than something physical like blood pressure.