[Q] Nexus 5 Boot loop Problem topic

Hello guys ,
My nexus 5 is facing some issues . Whenever i try to start it , It get stuck on the Team win screen in the beginning and it keeps appearing again and again . I am unable to start my phone . i tried to do ( volume down + volume up + lock button ) .. It switched off the phone .. but when i started it .. it again came to the same screen and again teamwin is appearing again and again . I dont know what to do . i was just unlocking the oem lock when this happened . Now i just want to get to the default factory settings .. please help me i am very scared and helpless .. Any helps would be great .. Thank You very much ..