Your doctor is right.
Yes, it is very much possible to conceive with one ovary. There are two ovaries, each one containing eggs. They take turns to release an egg every month. Thus, even if you have one ovary, it is very much possible to get pregnant. Your chances are high as long as the fallopian tube
that leads the egg to the womb is on the same side as the ovary present and also this tube should be intact. The single ovary will release an egg every month and the intact fallopian tube on the same side will catch the egg released. This helps you conceive, if you happen to have an intercourse.
As far as getting pregnancy
is concerned,couple of months are enough for body to heal after the surgery.You may proceed ahead with the plan and preparation of your pregnancy,as it is already two months since you got operated.