No,you cannot get an std from a toilet. It coldn't be an std unless you came in contact with someone elses privates. It could be a bartholin cyst.
Here, I found an article for you
on either side of the vaginal opening is a pair of glands called the bartholin or vestibular glands. The bartholin gland produces fluid that lubes the vulva's inner lips. Located on each side of the entrance into the vagina (introitus), this substance can ease penetration. If the opening to either of these glands becomes blocked, a bartholin cyst is formed that can make a bulge in the lip near the opening of the vagina. The cyst can also swell and become tender. Small, uninfected cysts may not have to be treated, but do need to be monitored by a health care provider.
Bartholin cysts can also become infected, forming what are known as abscesses. Abscesses can be excruciatingly painful and require treatment, such as oral antibiotics. Warm baths or compresses can help alleviate discomfort till your wife sees a provider. Cysts that cause pain or other problems can be drained by the provider by inserting a small tube (called a catheter) into the gland or by making an incision directly into the gland itself. In some cases, surgical removal of the bartholin gland is recommended, particularly for women with recurrent cysts. Fortunately, once cysts are treated with surgery, they're less likely to reoccur.
