Baby is so grumpy all the time..

My now seven month old is so incredibly grumpy all the time I'm really starting to think something might be wrong with him.. he's def a high maintenance baby but it's just getting so ridiculous I don't even know what to do anymore. He literally hates everything and will start whining if he's not constantly entertained from the moment he wakes up till bedtime. I know babies go through leaps and separation anxiety but this has been going on for about three months, every day all day. My husband and I are starting to dread going to get him in the morning and it breaks my heart but hearing him yelling and whining all day every day just starts to break down even the happiest. He's my second baby and I thought my first was high maintenance but he takes the cake.. he screams if he's doing tummy time for longer than a few minutes, gets frustrated at everything, gets bored of sitting after 5 mins, gets bored of every toy we have after 2 mins, is ok being walked around as long as there's something new to show him every few minutes or even then he starts getting angry, he likes to go for a walk in his stroller for 30 mins max and then starts death metal screaming and flailing around till you carry him, he hates his carrier, he hates sitting in his high chair.. the list goes on and on. Even in the bathtub with his two year old sister playing he gets angry after a few mins. I'm just so drained and exhausted with him I don't know what to do anymore. How many more months 😩 his doctor just laughs at us and says he's fine.. so nothing wrong health wise that she can see either. Just so grumpy.