My daughter is 15 months old and we have been through this stage several timess.
Just like your little one. My daughter has put herself to sleep in her crib since she was very young. I just lay her down with her pacifier and she goes to sleep no problems. But every once in a while - she has a couple of days in a row where she will cry and want to be held and rocked. So I hold and rock her for a couple of days. Then it passes and she goes back to going in her cirb and going to sleep. It is usually about 3 days. It seems to go along with a tiem when she is very much into mommy and doesnt want daddy or anyone else.
Just this week my daughter had about a week straight where she screamed every night when I put her in the crib. I went back to rock and sing for about 4 nights but it wasnt getting better. So I had to let her cry it out. It took 15 minutes the first night, then less than 10 the second night and 2 minutes last night.
I wouldnt have let her cry it out at a younger age- but at 15 months. she knows the routine of bedtime and she is old enough to be manipulate mom and dad.
Try giving extra cuddles and rocking for a couple of more days and if she continues on with the crying - you may have to let her cry for a night or two. -Just make suer that she is tired when you put her to bed. So she is likely to go to sleep after a few minutes of crying.