We are due to go on holiday next week (first in 8 years), and unfortunately pre teen DD (12) is due her period on the day we land. My friend told me about Norethisterone to delay periods. I started her on them today (she took her second tablet at 2pm) and now one of her calf muscle is red, hot and a bit swollen. I really worried about side effects now as I guess this is an unusual reaction?? Would I need to take her to A&E?