Pasta and rice are high in calories and carbs, so if you're trying to lose weight, stay away from them and eat low-sugar vegetables instead. You didn't list ANY fruit or veg in what you eat, so try and start consuming at least one portion with each meal. If you only just started exercising 3weeks ago and never did before that, your appetite has probably shot up to deal with the extra energy your body needs for working out. Keep an eye on your portion sizes. You say 4 small meals a day, but a small portion of meat is only 4oz, and a serving of cooked rice is just HALF a cup; the majority of people underestimate how much they eat. Conversely, not taking in enough nutritional calories a day will make you not lose weight too, as your metabolism slows down to deal with the lack of available energy. Use a BMR-calculator to work out the range you should aim for to begin with (there's loads online, just google it). Another thing is make sure you're drinking enough water. Whatever your bodyweight in pounds is, drink half that amount in ounces EVERY day to stop water retention which gains weight (i.e. if you're 140lbs, drink 70oz water).
Hope some of that helps!
It's most likely with the limited information you have provided that you are building muscle which weighs more than fat keep going to gym and doing light weights with lots of repetition rather than heavy weights with low repetition it's going to take time and after only three weeks i wouldnt expect a big result in weight loss and some weight gain is common and is usually attributed to muscles gaining density(weight) so you probably have lost fat but gained in muscle anyway Keep At It, it's worth it - God Bless