In your case you worked on Friday before your leaves (hope I am right here) and you worked on Wednesday after your leaves. So your week-offs and Holiday leaves are not covering from both end. So this will not counted as sandwich leave.
10th January 2019 From India, Delhi
In simple words, it is a group of continuous leaves you have taken before and the after week off's.
for Eg: if an employee has taken leave on Friday and Monday and in between there are weekly offs (Saturday and Sunday) then this 2 week off's are coming in between Friday and Monday will also be counted as leaves and total leaves will be counted as 4.
10th January 2019 From India, Chennai