Pill yes or no ?

Hey girls. My period has been pretty irregular, I will track it and get it earilier or later than its supposed to be. Like just yesterday I got it and it was one week early! I really hate it especially because I travel a lot and it can ruin a vacation. My doctor suggested I go on the pill and that it would regulate it. What are your experiences ? Everyone tells me not to do it cause it makes you gain weight. Have any of you gained weight while on the pill? Does it make losing weight harder (I'm a gym addict)? Any other side effects? Please tell me what it was like for you 😊 Thank you