Given the knowledge I obtained through years of applying to residence permits and visas, I can say (in my non-expert opinion) that this was to be expected. If I were your case officer, I'd have reported enough red flags for you to have a negative decision. Let's see the reasons they've given you:

1.Justification for the purpose and conditions of the intended stay was not provided

Where are you going to stay? Have you given attached an invitation from your boyfriend to the application? How are you going to spend on yourself in that time? Have you attached a bank statement from your boyfriend?

2.Your intention to leave the territory of the member states before the expiry of the visa could not be ascertained

Studies almost done, portable business, bank account very recently opened, Kenya is a high-risk country when it comes to that so your application was even more scrutinized.

I cannot see anything in your case that makes me believe that you're going back to Kenya when your visa expires. Basically, that's what you want your case officer to believe.

To add to this, now your refusal is in VIS (Visa Information System) which is shared amongst Schengen-area countries. This means that you have even smaller chances being granted any future visa to any country in the Schengen area.

If you don't work on demonstrating stronger ties to Kenya and provide means of support for your visit, then there's little to no hope of you getting a different decision.