Refusing to nap

This has been going on for almost two months and I'm exhausted. My baby refuses to nap and when he does go down it takes an hour and he will only sleep thirty minutes. He's rarely happy because he's so tired. He sleeps okay during the night will wake up a few times but can be pretty restless. I never let him go longer than 90 minutes awake and he can be yawning, rubbing his eyes, and closing his eyes but the moment I put him down for a nap his eyes are wide awake and he starts smiling which turns into screaming 10 minutes later. I can't get anything done during the day. I can't even put him down for a moment to go to the bathroom. My husband has gone back to work and I feel like I'm going to lose my mind. He does have gassy issues but gas drops and gripe water do nothing for this kid.