Baby puts pressure on the marriage

So me and my husband have been together a total of 4 years (together 3 and married 1). This year we had our first child (will be our only child) and it has been a really hard on our marriage. We don’t get to spend hardly any time alone anymore and between us getting up in the night and me being a SAHM I am exhausted. My husband also works and is always tired. I just need some advice on how to get our relationship back to what we were before. I feel like we have lost who we are. We love our son but it’s been hard.