I have a squishy lump on inside of left elbow do i need to worry?

Sounds like: Bursitis, but can't tell for sure with your description. Show it to an orthopedic surgeon because this could get infected. And it could be something else.

Olecranon bursa: It sound as if you are describing an olecranon bursa. They are benign . It could be aspirated and then a compressive dressing applied for a few days and that should relieve it. Otherwise prolotherapy to the bursa will close it down. It is not a cause for worry.