Mourn the loss of my beard.
Realise I am mourning nothing of great importance that mostly only exists because of laziness.
Figure out how I am going to explain this now my identity documents no longer have me as what I started as and this is probably as unexpected as coming back from the dead. Probably have to figure out chest binding as well. Also have to train myself to not walk up to urinals unless I can make a realistic she wee or something. That said I have never had to drop trousers before so I would probably be OK for domestic things, international for US style security theatre might be more troubling. Unlike identity theft I am not sure I have the real world people to say "yep definitely was penis owner at one point".
If I could (or needed) then get myself sterilised, whether that would trouble later experiments I do not know and would have to be accounted for. Pregnancy sounds thoroughly unpleasant so best to avoid if I can.
Decide whether to live in secret and just experiment upon myself, go full public science mode or go secret science cabal mode. If I did go full public science mode then having to figure out how to be even more boring so as to leave it as only science and no tabloid nonsense. If tabloids did happen then do my very best to offend the religious weirdos that would take offence at my mere existence in this state.
Realise I am not much of a biologist.
Spend 4 years becoming a biologist, hopefully this change would prove enough motivation to stick with it despite not especially enjoying biology, and especially not human biology, anywhere near as much as the sciences I did pursue.
Figure out the extent of the changes and if I expect any fallout from them, including psychological changes. Also have to see if any existing flaws made the transition and also what traits made the transition. Would probably attempt to start this right away and would try to take and store tissue samples, scans and more as soon as possible -- I might not know what happened or be able to do read much of it but I would know enough to do that. Part of that would also be genetic testing against my relatives to see what goes.
Figure out what happened to cause the change and if I could replicate it, I imagine such a thing would be fairly lucrative though if I could I would probably give away the end results.
Figure out what happened to see if I could reverse it, in the end I might not care but having the option would be nice.
Realise I just wasted time doing biology when I could have been doing something I really enjoyed. I might revise the above to include the option to be poked and prodded by scientists that like this biology lark, would rather not be whisked away to be never seen again though so might have to figure out something there.
EOF so song. Alas I am not sure if I have any songs about waking up as another gender
Edit there is a line in