My condolences. In this time, you will probably be feeling a tremendous morass of conflicting emotions. Remember that it was your real mother who died, not an idealized version of all "mothers" - not what Hallmark tells us exists when Mother's Day rolls around.
Also, you might consider giving yourself permission to grieve, not only for the loss of the mother you had, but for the mother you wanted. Often, the grief for the parent we wanted to have is far more overwhelming than the grief for the parent we actually had.
Much much support sent your way.