Thank you for sharing your question and photograph and I am sorry that your current results have caused you concern. It is common to still have difficulties in standing completely upright after a tummy tuck at only 7 days and is largely due to the muscle repair portion of the procedure. As you mentioned, each day should bring steady improvement in being able to stand upright. The dents that I see your photograph look to be the result of your remaining stretch marks and some pleating from the stitching performed. This will improve with time as your skin regains its normal elasticity and the tension placed along the stretch marks lessens. Hang in there!
Since you only posted a very limited view of your abdomen, it's hard to answer your questions. However, I will say that drainless (or Hollywood) tummy tucks typically have multiple "dents" in the initial post-op period due to the internal stitches that are holding the skin down to the muscle. When the stitches dissolve, all the dents resolve (usually within 3 months).