Eating well, lifting weights, swimming, GAINED 15 POUNDS???

Hello everyone, so I am 5’9 23yr old woman and have always struggled with my weight since a child. Recently (past 2 months) I have really locked in and have been lifting weights 5ish x a week and swimming at least 3, eating 1.5 times a day to stay in a calorie deficit. I started March around 210lbs and I just weighed myself today at the gym and I’m 230? What am I doing wrong? I know people saying lifting weights makes you gain weight because “its all muscle” but 20 pounds seem extremely excessive considering before I was just eating intuitively, not really watching calories and now I am and I’m the heaviest I’ve been in years. Any advice??? Please help, this is so frustrating.