Help! My Girlfriend Has Been Acting Strange Lately

Let me not bother you with too much stories, I will keep it short and concise.

My girlfriend has been acting strange lately and I couldn't find the reason why she's doing so. We started dating last year while I was still looking for admission, things has been going smoothly for us not until after ileya festival.



Before then, she celebrated her birthday on the 23rd of August this year had to sent a message to wish her, although I was around for ileya holiday as we both live in ibadan but am schooling in osun state.
She came to visit me on ileya festival(friday) which we talk extensively about her birthday, we both discuss on how to celebrate her birthday since I wasn't around then so we resorted to go to the cinema and have some few drinks.

Also, I promised to get her some women undies as a gifts before I left for school.

I ought to have been in school by now because the festive holiday has come and gone but have told her that I would love to spend some days with her before I leave. Before she left my house of friday I asked where she will be for the weekend, she told me she won't be around on saturday but sunday will be okay so I made up my mind to visit her on sunday and use the opportunity to see her mom and sibling.

I called on saturday to check on her but she inform me that she couldn't go out due to headache, the following day which was sunday I called her severally she didn't pick my call neither return all the messages I sent to her not until yesterday when she picked and told me that she intentionally not to pick my call because I wasn't caring enough for her. Asjed her what exactly have I done wrong, she said I didn't care for her meanwhile have been calling since sunday just to check on her but she didn't pick my call, mehn I was shocked!!.

As a gentle guy wey I be I asked for frogiveness and repeatedly told her "I'm very sorry" countless of time she cut off the line on three occassion, I was very furious by her action yet I keep cool had to call her once again she told me there's nothing she wants to discuss with me anymore except what she just did.

Till now, she hasn't pick all call neither reply my messages.

Now, have bought those things I promise to get her like pads, panties, bra, bum-short, and those girly things I even sent a text to inform her that have gotten her my promises she didn't reply me.

Pls I need your advice on how to go about this because it making me so sad.