There are three versions this year, the nasal spray which I guess is for children, ordinary (quadrivalent, ie protects you against 4 strains of flu), and adjuvanted trivalent (which is supposed to be more effective and protects against 3 strains). The last one is for over-65s and anyone else at particular risk. I had the over-65s version. I had a sore upper arm for a few days, and felt a bit tired for the rest of the day after I'd had it. No problems apart from that, and I have had no problems at all in previous years. It might have been because I had the adjuvanted version that I got the sore arm.
JP x