Bearing down & vaccum application causes stress
to vagina leading to injury/swelling of the part.But that reseeds no normal in maximally 8-10 days.
You you have the medium sized bumps on vagina, noted while taking shower.
If this is not accompanied by other symptoms like back ache,white discharge,fever
,burning in urine---It is more likely to be a lax/loose vagina due to bearing down.
Do perineal exercises regularly,to give strength to vagina.
Take high protein,iron,calcium,vitamin rich diet.
Consult a gynecologist for physical examination.