First pregnacy..

Me and my bf were having sex once in a while with some hopes to conceive.. i noticed my perdiod was 5 days late but didnt worry that much cause it happened few months ago and ended up getting it so i decided to make a test and it came out positive ! We are both happy but im quite stressed and scared as im 23 and its my fist pregnacy.. im having cramps like i usually do in my period but a lot less painful tho and lower back pain.. I have an appointment in a week im just wondering should i be scared of these pains ? what have you experienced during your pregnacies ?