“Yes, you should be able to get it today without any problem. You can get the emergency hormonal pill free from GP surgeries, community contraceptive clinics, some sexual health clinics, NHS walk-in centres, some accident and emergency (A&E) departments, and some pharmacies.”
“There are two types of emergency contraception pill (known as the morning after pill). Levonelle works for up to 72 hours after you’ve had unprotected sex, and ellaOne works for up to 120 hours. But the sooner you use it, the more effective it will be. You can also visit your doctor and have an IUD or coil fitted to protect you against pregnancy. This can be done up to five days after unprotected sex.”
You can find further information, here.