Hallow Dear,
Your description of the lesions is clearly suggesting a possibility of Bartholinitis. 
Bartholin's glands are situated under the 
labia majora. When they get infected, it is called as Bartholinitis. These glands have lymphatic 
drainage to the nodes in the groin, hence the lymph nodes in the groin also are swollen. If ignored, this infection progresses to form abscess(es). Such abscess(es) need(s) to be incised and drained. After incision the edges of the abscess are marsupialized to prevent recurrence of the abscess. 
Even after abscess formation, if the condition is ignored, the abscess bursts during 
menstruation, only to fill back again. 
Most of the times, Bartholin's abscess is due to sexually transmitted infections like Chlamydia or 
Gonorrhoea. Hence, it is advisable to start the simultaneous treatment to both the partners. Also till the infection is not completely cured, sexual abstinence is mandatory.  
The possibility of Lymphogranuloma Venenum (LGV) also has to be kept in mind as inguinal lymph nodes are also involved. 
Please report to your Gynaecologist and/or STI consultant. If the abscess is not formed yet and the infection is in 
cellulitis stage, it may be cured with a course of antibiotics, may be with Penicillin or 
Ampicillin. 
Another sexually transmitted infection - 
Syphilis is also known to go along with Gonorrhoea. It has longer incubation time. Hence it may take time to show its occurrence. Therefore it is advisable to take full course of the antibiotics (Penicillin, preferably) to take care of probable syphilis also. 
I hope this helps you.
Dr. Nishikant Shrotri