This one might be a little confusing. So I beat the Ecruteak City Gym Leader and moved on to the next city, Olivine. But then I found that there was a sick Pokemon there so I had to go to another city, Cianwood, which had a good pharmacy (the Gym leader in Olivine was watching over the sick Pokemon so I could not battle her yet). I got the medicine, but there is also a gym leader there so I'm trying to beat him, but he is sort of hard.