Lower face sagging and jowls appeared after the small size silicone chin implant removal. I am 25. What should I do? (Photo)

Most likely that deformity you describe is related to surgeries (implant placement and removal) that you had. It may take few more months for this temporary deformity to subside. It is unlikely that you will have any residual deformity. Jowls, if present 6 months after surgeries, can be addressed with conservative liposuction with small cannula. Be patient. Good luck.

You are a candidate for ONLY IN PERSON examinations.. Not over the internet. Plus at age 25 only Thread Lifts with fillers or fat grafts are indicated, not a facelift!

 I have performed many Chin Augmentations using chin implants for over 30 years.  From the photos, your chin is weak.  A weak chin creates an imbalance making the nose appear larger, the mid face top heavy and the lower face look short that de-emphasizes the lips and allows early formation of a double chin and "pseudo-jowls".   Pseudo jowls differ from "jowls" in what causes them, what they represent and how they are best treated.  Pseudo jowls are defined by a fold of tissue laxity that goes from the corners of the mouth to approximately 1/3 or 1/2 the distance to the lower jaw line.  It’s caused by a weak chin and its lack of tissue support around the chin and mouth area.  It's best treated by correcting of the weak chin with a silastic chin implant (or precisely placed dermal filler).  Jowls are described below in greater detail.  Chin augmentation using a chin implant will add projection to the chin creating harmony and balance to the lower face. 
 I have found that placement of a silastic chin implant, through a small curved incision under the chin (also allows excess skin removal) to be very safe, quick, highly effective and far less invasive than a sliding genioplasty.  I perform chin implant surgery in 30 minutes or less, often using a local anesthetic alone.  In my opinion, you are a good candidate for chin implant surgery.
 The back portion of your jaw line is a bit weak and can be augmented, without making your face appear masculine, using precise placement of a dermal filler (I prefer using Restylane Lyft).  Finally, a Closed Rhinoplasty can reduce the dorsal hump and refine the nasal tip (thin and slightly elevate the tip).
 "Jowls” are sagging facial tissues and an indication for some form of a SMAS facelift.  The underlying SMAS layer, of the face, must be dissected, lifted, trimmed and re-sutured (not merely folded or suspended with threads or sutures that will not last).  The excess skin is then removed and the facelift incisions closed.  While not impossible, it's unusual for "jowls" to be present in a 25 year old face, nor are they formed by placement/removal of any sized chin implant.  The are formed by laxity in the SMAS muscle layer.
My most popular facelift is the minimally invasive, short incision facelift that has all the benefits of more invasive facelifts (traditional, mid-face, deep plane, cheek lift and subperiosteal facelifts) but with these added benefits:
very small incisions and no incisions extend or are placed within the hair.
minimal tissue dissection = less bruising and swelling = rapid recovery ( several days instead of weeks or months with the more invasive type facelifts mentioned)
can be performed in 90 minutes or less, with or without general anesthesia
no incisions within the hair = no hair loss
excess fat can be removed
excess skin removed
cheeks, chin and jaw line can be augmented with dermal fillers (I prefer Restylane Lyft) or facial implants
most patients fly back home to parts all over the world in as little as 3 days post-op
I combine facial shaping with every facelift procedure.  When jowls are present, these should be done in concert and not alone or separately in order to create a naturally, more attractive face.
Hope this helps.