When my penis is erect sometimes around the base of it near the sack it hurts a bit but only some times, please help

If it is a real concern you need to see the doctor.

Hi, rando,
This is normal sometimes, if the penis has been erect for some hours! Or, if it has been erect, then recedes and later is erect again, on and off for awhile. The fluid buildup can cause an "ache".
If that isn't the case, you might consider seeing a Doctor.
I do wish you the best of luck.

O OK ty fredge that's what happens on and off ty I was a little worryed