You might owe nothing (if the basis is essentially the same as the amount you received), but you will not know that unless and until you contact the estate administrator (or other responsible party).
You should also receive a tax reporting statement if this issue had been handled properly.
Frankly, you should contact a local attorney that specializes in estate planning (probate matters, et al) since you also have no idea whether one or more parties is trying to pull a fast one on you (it happens more than anyone would care to admit). You can find a lawyer by using the link below and look for one who offers a free initial consultation.
https://www.avvo.com/probate-lawyer.html
