Am i normal?

I am 18 weeks and 1 day today. The last few days ive just been feeling really down and feeling extremely insecure. Crying over nothing, then crying more because i feel silly for crying about nothing, and the cycle repeats. Today, i woke up feeling sad, worn out, and tired. I'm anxious and just feeling run down/no motivation. This is our first baby and my poor fiance is just confused and doesnt know how to help and honestly i dont know what would even help. A couple of my friends and family said they got this way too but i wanted more opinions. Thanks!