Welcome Serenity!!
Em---> All babies are different. I know it's easy to say "relax" and not so easy to actually stop worrying
Elyse is 2 weeks behind LeeAnne, and she is not the most exciting baby ever TBH lol she mostly eats, sleeps, poops (like clockwork between 4pm & 5pm daily)..
She doesn't mind tummy time but I put her down on her tummy to sleep for naps & at night (tsk tsk to me!!)
She does put weight on her legs like to stand up when I hold her like that, she does smile and hold her head up well (but she needs to get better at it still, I can only put her in the Bumbo for a few mins at a time and if she's tired there's no way, she sits like a drunk in it, LOL)
But... she doesn't laugh, hold toys really (I actually worry that she's only interested in her mobile and her aquarium most days!), and she doesn't really push up on her arms during tummy time. And, sometimes when I put hold her so she can put some weight on her legs, she just flops over. TBH she really only does it for a few seconds at the most. I give her LOTS of opportunities to do this though, so maybe just try doing that with her more often? I bet LeeAnne CAN do it just doesn't know she can yet/doesn't feel like it, bc Elyse certainly has lazy moments where she won't do it!!
And LeeAnne is growing beautifully. Elyse is a dinky baby still, I don't think she'll be in her 3 month clothes until July. The bigger 3 month clothes probably not til August (she'll be 5 months in August actually)...
LeeAnne is perfect. She's happy, healthy, and remember with babies there's such a vast range for reaching most milestones! She's also teething early- I don't know about you but if I had teeth coming in I wouldn't want to be doing all that stuff either!!
If you want to look at stuff like that I recommend what to expect the first year (book), it tells you what babies should be able to do, will probably be able to do, and might be able to do month by month