If your surgeon is experienced, they should be able to revise this to your liking.
Generally this approach is very good for lengthening the lower eyelid. However, it is still an aesthetic procedure. This means that thought and care is needed to design the shape of the hard palate graft. Some surgeons make essentially no effort to shape the lower eyelid spacer graft. This can lead to over correction. The graft can be adjusted at a second procedure but yes, this involves additional surgery.
It is difficult to know if your repair is overcorrected without photos. It is likely not going to change much at this time (3 months) but I would not rush into any correction if it is subtle until at least 6 months. Scars do have a tendency to contract. Your surgeon is probably the best person to assess this.