Okay, so you're not sure what you're adding or losing. And you say your clothes are fitting tighter. I'll be honest if you don't mind
It could be anything. You don't really provide a detailed workout plan or how long you've been doing it etc. Sometimes when we first start working out we can gain a bit of weight. Maybe that's it. I don't know.
You could be eating too little. You don't mention how many calories you're taking in. Eating too little and working out can cause the body to gain weight. Maybe that's it. I don't know
It could be that you are working out too much. Sounds like you have 5 days of cardio and 2-3 days of weights. Not sure what sort of exercises or reps or sets though. Maybe that's it....
21% body fat- what sort of scale are you using? One you hold in your hands or one you stand on?
How long have you been working out before you changed things? I always recommend people stick to one fitness program/way of eating for a month. Then re-evaluate things and tweak from there.
Sorry if I can't give you a straight forward answer... it's just that there are quite a few possibilities. Are you getting your period soon? That causes the weight to rise.
My basic advice is to get a good strength training routine and menu. Get one designed for you and your goals. Then stick with it for a month and re-evaluate. Otherwise you're just shooting in the dark with half-information and guessing.
You'll end up growing frustrated (you may already be there) and wanting to give up.