Their doses vary from drug to drug and study to study, and also vary with patient weight. They are all given directly into the vein. Risky, but can help in the case of a massive clot where other alternatives are not available and the patient will almost certainly die without some treatment. Afterwards, urination is painful for about a day. Most likely what's wrong is an infection.
Some infections irritate the urethra, causing painful urination and ejaculation.
In women, these organisms can infect the vagina and other reproductive organs, causing painful intercourse as well. Other possibilities include problems with the organs involved, such as injuries, malformations, other types of infections, etc. The best way to find out is to see a doctor and have an examination and culture testing.