Needing some advice

Ok I need someone to tell me I’m not crazy and it’s not all in my head. I was supposed to ovulate the 30 according to the app. Had intercourse with my partner the next day. Felt a little off after that but didn’t think anything of it. Two days later he told me that he had this weird feeling that I was pregnant like he did when his ex was pregnant with his oldest son. Friday I started cramping off and on which is weird. Breasts have been tender and I have felt nauseous off and on. Woke up with a headache a few days last week. But that could be due to my sleep schedule being messed up. Are these actually signs that it could be real or have I played this all up in my head causing symptoms that aren’t real? What you you think please help.