Still in shock

Heyy everyone so according to the app in about 5 weeks today I did have an ultrasound last week and they were able to find a small dot they believe is an embryo but despite that I keep wanting to take more tests they are all positive but I just feel like its unreal and I want that reassurance... that being said I've been symptomatic since about conception with nausea, heartburn, dizziness, tender breasts, vivid dreams, frequent urination, food aversion and sensitivity to smells.. basically you heard it I'm feeling it Haha.. is it normal to have difficulty believing you're pregnant? Does anyone else feel like they need to be reassured? And is anyone else terrified that they will miscarry? This is my first pregnancy and I dont know what to expect