I had a small pea size lump in my armpit which converted into a boil. after that i got swollen lymph nodes in other armpit and groin area, please advice?

Sounds like your body is trying to fight off an infection in multiple locations, so systemic infection is possible, rather than just 3 separate areas. Please call/see your doctor to discuss treatment options. Until then, keep your skin scrupulously clean, avoid excessive sweating since these are all in high-sweat locations and try to eat well and get enough sleep to help your immune system.