Diagnosed with syphilis

Okay so I'm having the worst panic attack ever. Earlier this week I was told my STD tests came back positive for syphilis! And I'm soo scared! I've already contacted the health department for further treatment but I'm still feeling so lost! It's been a while since I was last tested so I don't even know how advanced it is or from whom I got it. And how do I even let my past partners know? I just need some encouraging support please! 😞