You can try booting into Safe Mode which disables most third party drivers and login items.
To look for possible software issues run EtreCheck and post the report here using the "Additional Text" icon which looks like a piece of paper.
How did you setup the new SSD? Did you perform a clean install of macOS and manually install apps, or did you install macOS and migrate from a backup, or did you clone the original drive?
Try running the Apple Diagnostics to see if any hardware issues are detected. Keep in mind that the diagnostic may report an issue with a third party SSD. It does not necessarily mean the SSD is bad.
What issues were you having before you upgraded to an SSD?
Keep in mind a lot of SSDs are just low end budget economy models that may be as slow as a hard drive at times. It would help to know the make & model of SSD. If you post the EtreCheck report this information will automatically be included in the report.
Did you upgrade the memory as well or is your laptop using just the original Apple memory?