Unsure of Child’s Father

Hi, I recently found out I was pregnant the only problem is I am unsure of who the father is. I was single and dating and I had sex with one guy on March 8th about two days after my period and we used protection. About two weeks after I had sex with protection with another guy on March 19th. Fast forward I can’t remember the second time me and the guy on March 19th did it but me and the first guy did it again on March 31st (with protection). My first appointment is May 11th but the app is telling me 6 weeks. The second guy thinks it’s his and I’m panicking so bad right now 😭😭. What can/should I do?