Hi,
The degrees at shorter distance is more or less Cartesian coordinates. If big circles then need to worry about spherical.
From you code it seems your radius is small. The you can use normal circle drawing equation.
if StartX and startY is your reference decimal degrees (center point) then
for (int j = 0; j <= 360; j++)
{
endX = startX + radius * Math.Cos(deg2rad(j));
endY = startY + radius * Math.Sin(deg2rad(j));
}
endX and endY (in decimal degrees) are 360 points in the circumference. Here radius also in decimal degrees.
However this will not work if your circle is more than approx 0.1 dec degrees (>1000 meters). It could work for smaller radius