Worried

Woke up this morning with absolutely no pregnancy symptoms. I should be 8 weeks today and I’m really worried about miscarriage. I have my first appointment on Wednesday. My breasts have been tender since I found out I was pregnant and I don’t even have that! I’m also so constipated I can barely stand up.. should I be worried that the symptoms have went away? Heard that’s a sign of a missed miscarriage. No bleeding or anything, just concerned as this is my first pregnancy!