Sex issues

So my husband and I have been together 10 years this year and married a year next month. I gave struggled with wanting sex and feeling like it’s work not fun for a while. I hate telling him not now or no he’s mostly patient with me but it’s like I kicked his puppy. I’m sure it’s going to get worse as we just found out we are 5 weeks with our first child together. I have an 11 year old with evening activities and sports so that keeps us busy too. Any ideas to help with wanting it and not feeling like it’s a chore? I really do love my husband and I want to work on this issue before it tears us apart.