Anxiety

I haven't been diagnosed with postpartum anxiety but I have noticed my anxiety levels have increased gradually since I had my son and now that he's 12 weeks they are at an all time high. My husband just left with my son to go visit a grandparent for an hour or so & I couldn't go because I'm babysitting my niece who inconveniently doesn't have a car seat here. This is the first time he has been for a ride in the car without me and I am literally crying and sick im so worried. I know that is ridiculous because my husband drives us all the time, but I am so anxious over it. Someone please tell me they felt this way too. I feel like my husband thinks I don't trust him or that I want to keep the baby from his side of the family, but it's not that at all. I just can't stand being away from my baby. All I could think was what if this is the last time I get to hold him. Ugh this sucks.