Car rpm stutters after start in park only

[Henry22]

After I start my car up she will stutter and shake as if shes going going to stall, the rpm guage will jump from 0 too 2 back and forth for a about 5 seconds. Sometimes it seems like my lights dim slightly as well. If I throw it in drive or reverse asap after start it goes away in a second. This only happens when my car is warm too. Doesnt happen first thing in the morning or after cars been sitting 6+ hours. Thanks.