Baby doesnt sleep at night?

My 4 month old daughter has no problem sleeping on her own during the day for naps. But for the past few days when it comes to night time she will not let me put her down in her crib for bedtime. Sometimes she cries right away, other times she’s fine but then is away 20 minutes later...as soon as I pick her up she’s fine and sleeps in my arms.

Last night the only way I could get decent sleep was I allowed her to sleep between me and my husband.

Any suggestions? Tips? Advice? Should I start sleep training? Ugh!!! I’m exhausted!!! I