Because of the shape of the swelling, it doesn't look like its broken to me...but if you've torn a tendon that could be even worse.
The fact that you were able to cycle back following your "ordeal" indicates its not too serious, but as cettericksmiler said...RICE - by cycling back with it you would have increased the circulation and possibly aggrivated it...i know its not like you had much of a choice with that one though!
my prediction is a nasty sprain so sadly it wont get you off your exams!
I think you can take ibuprofen and paracetemol together, since you can get them in combined tablet form, but theres really no need for para....
ibuprofen is an anti-imflammitary drug, so it will be most effective, as the pain will be caused by excess fluid pressure on the joint, which will further aggrivate the injury.
dont worry though...crochet next week wont be affected (just stuff the crutches if you end up with them in the arm pits and you'll be ready to go....)