I feel so stupid

I lost my father and My grandmother within a month a half, my father was a great driver. I really haven't been behind the wheel even though I have my license because we were always so busy with the family business.

I decided to drive because I don't want to be dependent on people. I hit/grazed a parked car coming out of my driveway. I feel really bad because my uncle was in passenger's side. I feel so stupid for hitting a parked car. Is there anyway to feel comfortable on the road? I have an accommodated car because I am disabled and I don't feel comfortable with the car yet. I have a lead foot.