I think I may be hypomanic. Help?

All my life (60 years)I've been diagnosed and treated as a depressive. All my episodes have been depression. Then three months ago I did something nuts: I bought tickets for my partner and me to go to Germany to visit a friend for three weeks, with a departure only two weeks away.

And in that two weeks I had to write half a novel so as to deliver it and get paid before Christmas.

While I was buzzing around in that frenzy my partner, who is bipolar, announced to me that I was manicky. Who, me? The depressed one?

I have a family full of bipolars, from mother to cousin to partner and my kids. I know this is likely genetic, but still, I've always been depressed.

I can't take antidepressants at all (the ones that work for me elevate my blood sugar and I'm diabetic) and I can't afford to see a pdoc. So I'm asking my question here.

Over the last week or so, I sank again until on Monday I was barely functional, which brought me here. It's so important to reach out from depression no matter how hard it is, and with much of my family bipolar, I've learned they're not the ones to turn to. Especially my partner. She's hypersentive to my moods and too often mirrors them or gets annoyed.

So Monday I could hardly move. Monday night I slept as usual but woke up too early. It felt as if a switch flipped. I was no longer depressed.

Then I started buzzing.

As of yesterday, I felt as if I were on speed, thoughts racing, unable to focus for long, easily distracted, irritable as all get out. I found myself chatting too much with friends online, saying too much, and having to self-censor nearly everything I wrote. I was even having to stop myself from picking fights, and I'm not that kind of person usually.

I'm on day three now (I know it's supposed to last for four days to be clinical) but the first episode lasted over three weeks.

Is it possible to discover you're bipolar at 60? Is is possible to have been unipolar all your life and then have this happen?