Clothes tighter help!

Ok so ive been working out now for 3weeks (30 day shred) i workout 6x week 20mins a day. Recently i noticed my clothes fitting tighter on me. I dont have thyroid issues, i am not taking anything nor is it near ttom so im completley lost.
I need 1500 sedentary and 1660 with exercise so i eat 1360 a day to create a small deficit and i eat maintenence on my rest day.
I definitly can feel muscle tone improvement under my skin but no noticable changes in inches and the scale is still hovering around the same number.
I have felt bloated in my stomach area recently but would this cause my jeans to be fitting tighter? could it be that im holding water so late into exercising?? hope someone can help me this is discouraging! im not sure whether i should continue what im doing or stop

Do longer workout sessions. 20 mins a day?? What do these workouts consist of??? It doesn't seem nearly long enough to me.

Aside from eating clean six days a week and getting enough calories, what I would recommend is lifting on a full-body routine doing compound exercises with free weights. You keep the weight heavy enough to where you can only do 5-8 reps. Do this 2-3 times a week for 45-60 minutes a session.

The main exercises are squat, deadlift, bench press, standing military press, and barbel row. Also add in some compound bodyweight exercises like pull-ups. Split it up into two workouts and switch off between them on every workout. For example, workout A would be bench press, deadlift, and pull-ups while workout B would be squat, standing military press, and barbel row. Do each exercise for at least 3 sets. Keep switching off between both workouts, adding 5 pounds to each exercise everytime you complete all three sets with good form. Example - Mon (A), Wed (B), Fri (A), Mon (B), etc.. These are the exercises that will help you to build the muscle you need to firm up and lose the bodyfat you want to get rid of to fit into your clothes better.

You should also encorporate some form of HIIT (High Intensity Interval Training) into your workout regimen 2-3 times a week. Read more about it here : http://caloriecount.about.com/hiit-thread-pos t-all-questions-routines-ft143813

20 minutes of circuit training/calisthenics, there's basically 3 circuits consisting of strength, cardio and abs. I burn about 160 in that 20 minute session. What i meant was im eating clean i have a small deficit but yet my clothes are appearing tighter on me. Im on my 3rd week of exercising and im wondering if it could be water retention as ive noticed being bloated in my stomach for over a week now? it seems a little odd though happening 3 weeks in exercising and like i said i dont have thyroid issues, i am not taking anything nor is it near ttom so its pretty random. Should i continue doing what im doing or could it be that im actually gaining weight

Have you recently increased the amount of fibre in your diet?  If you're noticing your pants are tighter, it could be a bowel/gas/fibre related problem.  Also, are you measuring your portion sizes or just eyeballing them?  If you aren't measuring, then you might be eating more than you think you are and therefor don't have the deficit you think you do. 

One more thing, if you have only been exercising for 3 weeks you should probably give it a little longer before throwing in the towel, because changes in your body often take longer than you think to actually start happening.