Any rainbow baby mummas scared? 5w4d

Emma • A miscarriage pcos no periods for years. No guides. Advised no babies naturally due to issues then this little miracle
I lost my first pregnancy last year. After finally getting my life back together and just about to be referred to fertility clinic we found out that we are expecting miracle baby #2 after being told we probably wouldn't be able to conceive again naturally. 
I thought I would be ok but I'm feeling so stressed with every ache and pain. I'm having cramping and my hormones are crazy mad. I know the worse I feel the more my body is doing what it should but I don't feel like I can relax and enjoy this just yet, just in case. I'm in no way being negative in fact in quite positive with everything so far. Is anyone else feeling like this? Xx