I'm so sorry to hear about your loss.
I lost my maltese and for me I tried to replace her about a month later and I just couldn't get attached to the new pup, as a matter of fact I just didn't feel a connection to the new puppy at all because all I thought about was my lil girl. I ended up giving the new pup back to the original owners which worked out really well because they wanted him back really bad but it doesn't always end up that well and you end up with a pup that you may have to re-home and that can be really hard not only physically but emotionally. I'd say wait a little bit and grieve and then when your ready you'll know.