For all night wakings, even it is feeding time, give your little one 10-12 minutes to try to go back to sleep on their own. Because they went to sleep on their own at bedtime, this is a realistic expectation. If they have not gone back to sleep and it is not feeding time, then use the same strategy your did at bedtime: either come and go or sit and support until they go back to sleep. The first night or two the wakings may be long, but if you are consistent your baby will catch on pretty quickly. You should start seeing progress in 2-3 nights and the average for sleeping through the night is on night 5.