What Causes Incidental Focal Calcification In The Anterior Of Thecal Sac?

hi, i am 25 years old male, i do sports all the time, i had pain at my lower back, beacuse i was trying to lift a really heavy object, i went for a CT scan, and the report says :
1-No signs of static instability noted.
2- "LV5-SV1 mild posterior diffuse disc bulge slighlty indenting the ventral thecal aspect and slightly encroaching upon the inferior aspect of the corresponding L5 neural foramina on both sides"
3-Incidentally focal calcification is seen in the anterior aspect of the thecal sac opposite SV2 level, otherwise no Ct identifiable lesions within the thecal sac or the epidural and peri-neural fat planes.
4- small air focus is seen in the left iliac bone possibly air within a small bone cys.
5- no pre or para-vertebral lesions or collections identified.
6- Normal CT appearance of the apophyseal articulation.
7- No other significant disc bulges or herniations identified.
is it serious, and am i going to do sports anymore?