Post pardum anxiety

I feel like a nutcase! I’m usually doing okay but when we get invited to go somewhere that has a crowd I begin to get very nervous about taking my baby. I am so worried about him getting sick from other people. He is only 4 months. I miscarried before him and ever since them everything regarding baby scares me to death. I keep telling myself I will feel better about him being around others when he is older but I’m reality will I? Now that he’s here he is my whole world and I wouldn’t be able to handle losing him. I don’t want to live in fear forever and I know there are things in this world I just can’t control but it makes me cry a lot. I don’t seem to mind if like we meet with like one friend or so at a time but groups make me worry I also don’t mind if my close family hold him at all but for some reason when my husbands family even comments on my pictures of him that they want to snuggle him I’m like nope! What is wrong with me? Is this normal?