Should i let me get checked????

Two days ago I had sex for the second time he was pretty big and we didn't use a condom.. Today I took a Plan B/Morning afterpill. He told me that I would probably still feel it downthere but now im not sure if he means bc of how big he was or bc he gave me an sti/std and i feel this tinkle inside my vagina i grabbed a mirror and i couldnt see anything odd looking downthere but should i go to the doctor?