I need to lose 25 pounds!

So this year has been a little hectic for me. I started at around 129 pounds in August. With the course load I'm taking at school and the amount of homework I've had, I slowly but surely gained around 4 pounds from August 2015 to around December 2015 from a combination of stress and lack of excercise. During those months, I rarely excercised because I spent my extra time doing homework and when I wasn't doing homework I slept. I would also like to mention that I get around 5 hours of sleep a night, sometimes with a 1-2 hour nap during the day. So I started the new year with a weight loss plan to get down to around 125. From January to late March, my weight fluctuated between 135 and 139. I'm still getting about 6-7 hours of sleep a day and I excercised here and there but it's wasn't on a regular schedule or anything. I don't eat a lot, but I'm sure I snacked without myself fully realizing that I'm snacking. Anyways, spring break starts and I go out of town for my friend's wedding. It was constant eating out for about 5 days in a row, but I also managed to do about 20-30 minutes of cardio a day. When I got back I weighed myself and my scale was at a whopping 145. This was when I started paying more attention to what I ate, when I sleep, and how much I excercise. It's been one week since the wedding, I've done about 20-30 minutes of jogging every single day, and I've kept my caloric intake to about 1250-1400 a day, but now I weigh 153. I am honestly at a lost for words at how I managed to gain 8 pounds in a week with controlling my eating and excercising. This was twice the amount of weight I gained in 4 months for not excercising at all. Part of me feels like this could be edema (water retention) because throughout the day I have swollen feet and when I sit on an object it leaves about a 3 mm deep imprint of it on my leg for a good 5 minutes, but when I excercised the swelling automatically goes down.

Overall:
Height: 5'3"
Weight in August: 2015: 129
Weight in December 2015: ~135
Weight in March: Between 135 and 139
Weight In Early April: 140
Weight Now: 153
Caloric Intake Daily: 1200-1400 ( I usually start my day off with a banana, then another banana for lunch, dinner is usually 1 cup of rice/grain/pasta and some meat and veggies. My snack usually consists of veggies or fruits.)
Excercise: Treadmill ( I go for about 20-30 minutes a day, I do plan on increasing this time allotted in about 2.5 weeks after I'm finished with school and finals)
Sleep: 5-6 hours, sometimes with a 1-2 hour nap during the day
Stress Level: High because of school and stuff
Water Intake: I drink about 36-48 ounces a day.
Movement Level: pretty sedentary, I got steps in between classes but that's about it other than my daily jog.

I just feel really discouraged that the weight I'm at with excercising is higher than the weight I ever was without excercising. Half of the weight I gained in the past year were centralized to this month, even though I've excercised more this month than I've ever had this entire year. I have also decreased my caloric intake. I wasn't exactly sure how much I ate in 2015, but I do know that I have reduced for meals to be about half size with small snacks in between. I haven't drunk any sugary drinks. The only two things I drink now are water and green tea. I could sleep more but I can't control that until I'm done with school in about 2 weeks. I plan on joining the gym and excercising more but again that will happen after I'm done with school. I know this is long, but I'm asking anyone who's ever been through what I'm going through to tell me what they did to lose weight. I knew I was gaining weight this entire year and when I could excercise I did, and the results after a couple days were immediate ( like from 138 to 136), but now I excercise and weigh myself and it goes from 149 to 153. I just need tips on what I should do, and if I am retaining a lot of water what should I do about that.