Dell India — unsure about the product

So, i bought this pc from dell showroom some 2-3 months ago for some 35k. The inner specifications of the pc tell that it is inspiron 15 3584 but the sticker near the keyboard says it's inspiron 15 3000. I was told this was the slimmest inspiron ever. I feel a bit cheated. Please see to it and help me asap!. I desire a full explanation regarding it as it's my right and your duty. Also i didn't noticed any problem in the working of the pc, yea sometimes it's speakers do misbehave producing a chirrrreeuupp sound for a second or two. Else everything seems okay but i feel i"m handled with an older version pc while being promised of the latest pc.