In last few months I have observed I am getting red bumps/pimples on my body as attached in pic. All these bumps are appearing in my belly region They don't itch or pain but I am noticing it is increasing in number slowly day by day and size also growing. There are around 10-12 such pimples as of now. The largest size is the one which is attached in pic. What exactly is this and what could be reason for it? What I should do to control or cure this.