Every baby is different, not to mention that every baby & mommy combination are different, but I can share things that I found helpful with mine. But first I want to say that I am sure you are NOT a bad mom. I know the feelings of frustration and helplessneess. I felt that too, especially with my first baby, and sometimes even now with my toddlers. When I had my first baby, I heard "follow your instincts" so much and it made me feel more and more like a failure because I didn't have any instincts! I had no clue what to do and my "gut" wasn't telling me anything except that I was overwhelmed. This whole adventure of parenthood started a little over 3-1/2 years ago for me, and I can say now that experience has taught me a few "instincts," but I think it is really just the product of learning my new role in life and is not instinctual at all. I found some sources of parenting advice that I felt I could trust, and I followed the advice and am learning how to be a parent along the way.
As for things that worked with my babies, they could never stay awake (happily) for more than 2 - 2-1/2 hours at a time at this age, sometimes even less. Both of my babies usually needed their first nap only 1-1/2 hours after waking up in the morning. I never could understand how they could be tired so quickly after sleeping the whole night, but that is how it was. Both of my babies really enjoyed being swaddled (very tightly) even at this age. If you don't already do that, it is worth a try, and if at first it does not seem to help, give it a few tries to be sure. My first baby liked the pacifier and he would go to sleep in his crib with the pacifier with no problem. My second baby didn't really care for the pacifier, but he eventually found his swaddling blanket to be really tasty (he is 2-1/2 now and still sucks on it when he goes to sleep). There was some crying involved for both of my babies, but if you are going to do that, you need to have a "plan" with how long you will let them cry and how you will respond, otherwise it is fruitless frustration and anxiety for both of you.
A bedtime/naptime routine is very helpful to let the baby know that bedtime is coming. Both of my babies have really thrived on routines, they like the predictability. You can choose some "calming" things that you both enjoy to include in your routine, such as a book, singing, snuggling, bathing, etc. for the bedtime routine, and make the naptime routine a shortened version of the same thing.
The late afternoon/early evening was always a fussy time for both of my babies. With my first baby, we would always go for a family walk in the neighborhood during that time. He liked looking around and it kept him calm. It also helped us get through that "fussy time" until bedtime.
If you would like an extra resource of information, I have a book from an infant sleep expert that gives some helpful guidelines and ideas for helping babies to get on a good sleeping schedule and get the rest that they need. I found it pretty helpful. I have it as an electronic document so I could attach it to an email and send it to you, if you like, just reply with your email address if you are interested.
I hope this is at least somewhat helpful and encouraging. I'm sure you will get some good advice from the other moms here, too.