We are the same height and 100 lbs is NOT chubby. Watch your water retention and the sale and sugars.
Some foods will make you look "fluffy" try to maintain your weightor add good weight but shed some poufy...
Drink 1 gallon of water throughout the day..religiously
Eat good healthy meals...lower in salt and sugar than you are probably used to...
for example...
1- 6 oz skinless boneless chicken breast grilled or baked...nho frying, no oils and so forth
1 Cup of steamed green beans
1 C steamed brown or wild rice
1/2 of a baked sweet potato
That type of meal will give you plenty of protein, tons of good carbs and light in the fat area but still give your body the fat it needs in a meal. The water is the key. Most people think drinking water bloats you...not true. Your body needs the water to process your food properly and efficiently and it also helps the body burn fat deposits. Also, by feeding your body the proteins and good carbs, walking and so forth, will replace fat deposits with muscle...muscle is smaller than fat, so you can actually weight the same but look completely different. You can also gain muscle weight and lose fat weight and wear smaller clothes and look smaller and leaner. This is NOT a bad thing at all.
An example of a good breakfast....Oatmeal, some strawberries and a piece of fruit.
Also, eat smaller meals more often.... eat the smae amount you normally eat or even more but eat it more often throughout the day. ie: If you eat 2000 calories per day usually in 3 meals, eat that same 2000 calories in 5 meals....eat less more often and force your body to use what you give it. It increaswed metabolism and the body functions more effectively and efficiently.
But..seriously, do not worry about your weight dear, if you want the bikini shape..worry about the distribution of your weight.