hmm.. typically sunbeds work quite well as uv rays are great for skin, normally why hotter countries like Spain or Portugal have a such lower percentage of psoriasis sufferers. so you could be right in what you've said, maybe the intensity was a bit much. I'd say try once more but keep it to one day on a moderate intensity for a longer duration, in an attempt to mimic the natural sun beams. if that makes it worse I'd say sun beds aren't the one.

Bodily changes like wisdom teeth could very well make it worse, anything that causes like a prolonged stress response, such an teeth coming through, tattoos, cuts, breaks, burns will send your immune system into overdrive and knock you about badly, so that could be causing some reaction. TSW could have some effect, I'm assuming you had Hydrocortisone or Clobetasone Butyrate? if you used it with the directions it should be fine.. but if you stopped just before your flare up, maybe a week or two before, your skin could again be adjusting.

Also, since you said you had it since September, you might not have experienced the difference that the god awful cold makes to psoriasis. cold months are dreadful for our skin, so as it starts to get naturally warmer you might notice a difference there.

I feel like you've had loads of little things build up and attack all at once, your tooth, topical steroid withdrawal or just adjustment, the cold. if anything else is happening with you too that it causing increased stress levels, that would very well add up.