Do I have an std? I had sex for a few days and wasn't experiencing anything and now I have itchy, swollen, sore lump inside me, it's bloody and chunky

It is possible. With your symptoms, and for your piece of mind, see the dr. For an evaluation and testing of the discharge with a possible std panel being done as well. Best wishes.
Need an exam. No herpes or syphilis (the stds that can produce a lump) would manifest this quickly. It is more likely that you have an infected gland like the barthollin cysts that can commonly develop as you describe. Your physician should be able to sort this out for you!